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Designation of critical habitat is an important conservation tool for species listed as threatened or endangered under the United States (U.S.) Endangered Species Act (ESA). While this is an important protective mechanism, lands designated as critical habitat could still be subject to degradation and fragmentation if they are not also in a protected status that prioritizes biodiversity conservation. Additionally, most designations of critical habitat do not explicitly take climate change into account. The objective of our study was to determine whether and to what extent critical habitats for species listed under the ESA are located within protected areas and areas previously identified as climate refugia or climate corridors, to inform management strategies to better conserve and recover these species. We mapped the designated critical habitats of 153 ESA-listed species and measured their overlap with previously-identified areas of climate refugia and corridors (CRC), and also with lands designated as nature-protected by U.S. Geological Survey’s Gap Analysis Project (GAP Status 1 or 2) and working lands with wildlife habitat potential (GAP Status 3). Only 18 % of all designated critical habitat is located on lands that are both in CRC and nature-protected, and only 9 % of species had over half of their designated critical habitats in such lands. 84 % of species had

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Hong Kong is one of the busiest metropolises, and the Eurasian otter Lutra lutra is one of its most threatened species. We collected published data for 1890–2020 to document changes in local otter abundance and distribution over time. The 108 records revealed new distribution data and showed that decline began as early as the 1930s. The local Eurasian otter is strongly associated with coastal and alluvial wetlands, and its last refugium, the Yuen Long floodplain draining the Mai Po Inner Deep Bay Ramsar Site, has always been a critical habitat. Our analysis suggests that hunting is unlikely to be a major cause of the otter's decline. Rather, dependence on lowland wetlands makes it particularly susceptible to habitat loss caused by increasing urbanization. Auxiliary infrastructures and water pollution have also exacerbated wetland degradation to the detriment of otters and their prey. There is a need for greater cooperation amongst government agencies and landowners to guarantee otter survival: priority steps include the establishment of additional and interconnected wetland reserves, better stakeholder engagement and enforcement efficiency to tackle entrenched pollution problems, and flood prevention schemes that preserve or restore functional riverine ecosystems within critical otter habitats. The current otter distribution range has been earmarked for development in a government-led mega urbanization plan; the plight of the local Eurasian otter needs to be widely publicized to garner stakeholders' support and galvanize immediate conservation actions across society.

Seagrasses are globally acknowledged as crucial habitats as they provide a variety of ecosystem services. Mexico's legislation protects most of these marine plants; however, the protection often fails in application. The Gulf of California, despite being a biodiversity hotspot, has scant data on seagrasses. Here, human activity and climate change increasingly threaten these coastal ecosystems, with conservation and research efforts lacking coordination at a regional level. Our manuscript aimed to review and standardize existing data on Gulf of California seagrass species, ensuring open access for data updates; pinpointing conservation deficiencies; and guiding future research. We have added new records to the official public data, but we were able to recapture only 25% of the seagrass locations meaning a potential reduction in their historical distribution of 45.8%. Even though Mexico's legislation protects some species of seagrasses, it protection often fails in the application. We identified that only 6.1% of the seagrass locations are within protected areas that recognize their presence in their management plans (e.g., the Balandra Flora and Fauna Protected Area and the Upper Gulf of California and Colorado River Delta Biosphere Reserve). At least 55.9% of seagrass records are associated with potentially damaging activities like pollution, coastal modification or biological resources use, while 23% are exposed to higher frequency of marine heatwaves. Given the importance of seagrass meadows under Mexican law and their internationally recognized ecological value, sharing current information and guiding research is essential. Our study seeks to galvanize renewed research initiatives and raise more awareness on the conservation of the Gulf of California's seagrasses. [ABSTRACT FROM AUTHOR]

Hong Kong is one of the busiest metropolises, and the Eurasian otter Lutra lutra is one of its most threatened species. We collected published data for 1890–2020 to document changes in local otter abundance and distribution over time. The 108 records revealed new distribution data and showed that decline began as early as the 1930s. The local Eurasian otter is strongly associated with coastal and alluvial wetlands, and its last refugium, the Yuen Long floodplain draining the Mai Po Inner Deep Bay Ramsar Site, has always been a critical habitat. Our analysis suggests that hunting is unlikely to be a major cause of the otter's decline. Rather, dependence on lowland wetlands makes it particularly susceptible to habitat loss caused by increasing urbanization. Auxiliary infrastructures and water pollution have also exacerbated wetland degradation to the detriment of otters and their prey. There is a need for greater cooperation amongst government agencies and landowners to guarantee otter survival: priority steps include the establishment of additional and interconnected wetland reserves, better stakeholder engagement and enforcement efficiency to tackle entrenched pollution problems, and flood prevention schemes that preserve or restore functional riverine ecosystems within critical otter habitats. The current otter distribution range has been earmarked for development in a government-led mega urbanization plan; the plight of the local Eurasian otter needs to be widely publicized to garner stakeholders' support and galvanize immediate conservation actions across society. [ABSTRACT FROM AUTHOR]

There is no current population estimate for Risso's dolphin (Grampus griseus) in Scottish waters and their distribution in the northeast of Scotland and the Northern Isles is poorly documented. Using a combination of citizen science and historical sightings data, photographs of Risso's dolphins from northeast Scotland and the Northern Isles were gathered to gain an indication of the presence of the species in this region. A review of all available sighting records from as early as 1933 (n = 1,904 records), showed a historical presence of Risso's dolphins in the study locations, with a notable increase in sightings reports over time and with higher numbers of sightings reported from July-September. Collation of photographs (n = 1,884) taken by members of the public and researchers facilitated the establishment of two photo-identification catalogues for Northeast Scotland and Orkney (n = 112 individuals) and for Shetland (n = 47 individuals) respectively. Mother/calf pairs were recorded between April and November. Repeated recaptures of identifiable animals throughout the study area provided the first evidence of inter/intra-annual site fidelity. The combined datasets demonstrate the potential importance of inshore coastal waters in northeast Scotland, Orkney, and Shetland as critical habitat for Risso's dolphins. Recommendations are made for ongoing monitoring studies to inform the protection of Risso's dolphins in Scottish waters. [ABSTRACT FROM AUTHOR]

Simple Summary: Wetlands are one of the most important habitats for waterbirds. Due to the increase in human activities, waterbird habitats have been severely disturbed. Limited availability of human and natural resources makes effective habitat protection particularly important. Therefore, in this study, we developed an index system to evaluate habitat waterbird importance in Anhui Province based on habitat status. This allowed us to identify distribution and change patterns over time in important waterbird habitats. We also examined gaps in the protection of these crucial habitats and identified the key environmental influences. We found that Anhui Province has 73 important waterbird habitats, mainly concentrated in the Yangtze River floodplain. Gap analysis showed that 42 of these suffered from protection gaps, accounting for 57.53% of the total area. The importance of waterbird habitats was significantly correlated with elevation, normalized vegetation index, lake area, and lake circumference but not with distance from roads or population density. This study presents scientific information for waterbird habitat conservation in Anhui Province and provides reference cases for waterbird habitat conservation and maintaining wetland ecosystem functions. Wetlands are among the most important habitats of highly wetland-dependent waterbirds but are subject to ongoing habitat loss and degradation owing to intensified anthropogenic activities. The scarcity of human and natural resources makes effective habitat protection an important concern. Here, we aimed to investigate waterbird habitat protection methods for Anhui Province, China, a critical stopover and wintering area on the East Asian-Australasian Flyway that features rich wetland resources subject to significant habitat loss and degradation. We evaluated the status and importance of 306 wintering waterbird habitats and identified the key environmental influences and current protection gaps using the entropy weights method and generalized additive modeling. We found 73 important habitats for waterbirds in Anhui Province, which were classified into levels of importance (descending from I to V) according to the natural discontinuity method. Level I and Level II habitats were mainly located in the Yangtze River floodplain and Level IV habitats in the Huaihe River floodplain. The gap analysis showed that 42 important waterbird habitats had protection gaps, accounting for 57.53% of the total area. Waterbird habitat importance was significantly correlated with elevation, normalized vegetation index, lake area, and lake circumference but not with distance from roads or population density. The results of this study provide scientific information for waterbird habitat conservation planning, which is crucial for maintaining wetland ecosystem functions. [ABSTRACT FROM AUTHOR]

The persistence of threatened wildlife species depends on successful conservation and restoration of habitats, but climate change and other stressors make these tasks increasingly challenging. Applying climate change vulnerability analyses to contemporary wildlife management can be difficult because most analyses predict direct effects of future climate on wildlife species at broad geographic scales, rather than assessing their habitats at local scales (<1 km) that correspond to site‐specific habitat management actions. We present a framework that synthesizes vegetation‐focused vulnerability assessments to assess multiple effects on wildlife species' diverse habitat needs, providing a scenario‐driven climate vulnerability assessment that maps differences in vulnerability of populations within a species' range. Our flexible habitat‐centered synthesis approach leverages available spatial datasets describing projected exposure to vegetation changes due to climate change and other potentially synergistic stressors, reclassifies and weights them based on available estimates of species' sensitivity to these changes, and recombines them to create <1‐km resolution maps of overall species vulnerability and threat‐specific habitat vulnerability. To demonstrate its potential to guide decision‐making, we applied this approach to the Gunnison sage‐grouse (Centrocercus minimus), a federally threatened habitat specialist that depends on sagebrush and mesic habitats that are imperiled by climate change. We mapped six threats forecasted out to the year 2070: direct effects of climate on (1) sagebrush cover loss and (2) mesic habitat drying, indirect changes in invasion risk from (3) pinyon–juniper conifers and (4) annual grasses, and potentially synergistic risk of (5) development and (6) wildfire. We then assessed species vulnerability for each of the eight extant populations under three climate scenarios: Optimistic, Continuation, and Pessimistic. We found that the extent of cumulative species vulnerability due to multiple habitat changes was far greater than the extent of any single habitat vulnerability. Over 75% of critical habitats were at risk under the Pessimistic scenario, and nearly two thirds of habitats were at high risk for three or more threats. Invasive species were the most widespread threat, highlighting the importance of indirect effects of climate change. We illustrate how our approach can be applied to the existing management planning strategies to better prioritize conservation of habitats for the persistence of threatened species. [ABSTRACT FROM AUTHOR]

To recover species at risk, it is necessary to identify habitat critical to their recovery. Challenges for species with large ranges (thousands of square kilometres) include delineating management unit boundaries within which habitat use differs from other units, along with assessing any differences among units in amounts of and threats to habitat over time. We developed a reproducible framework to support identification of critical habitat for wide-ranging species at risk. The framework (i) reviews species distribution and life history; (ii) delineates management units across the range; (iii) evaluates and compares current and (iv) potential future habitat and population size and (v) prioritizes areas within management units based on current and future conditions under various scenarios of climate change and land-use. We used Canada Warbler (Cardellina canadensis) and Wood Thrush (Hylocichla mustelina) in Canada as case studies. Using geographically weighted regression models and cluster analysis to measure spatial variation in model coefficients, we found geographic differences in habitat association only for Canada Warbler. Using other models to predict current habitat amount for each species in different management units, then future habitat amount under land use and climate change, we projected that: (1) Canada Warbler populations would decrease in Alberta but increase in Nova Scotia and (2) Wood Thrush populations would increase under most scenarios run in Quebec, New Brunswick and Nova Scotia, but not in Ontario. By comparing results from future scenarios and spatial prioritization exercises, our framework supports identification of critical habitat in ways that incorporate climate and land-use projections. [ABSTRACT FROM AUTHOR]

Limiting disturbance in critical habitats is an important part of ensuring the well-being and sustainability of populations at risk, such as Cumberland Sound beluga whales (Delphinapterus leucas). Using non-disruptive Very High Resolution (VHR) satellite imagery, an emerging tool in cetacean monitoring, we aimed to estimate summer abundance and identify critical habitat for Cumberland Sound beluga whales. Specifically we looked in fiords that comprise their summer distribution, such as Clearwater Fiord where there is a large estuary, an important habitat to many beluga populations. Satellite images of the area were collected in 2020 and 2021, at 30 cm resolution, and in 2022 at 50 cm resolution. We evaluated beluga whale distribution using Kernel density, and identified critical habitats as areas consistently part of the beluga whale core distribution across years. Clearwater Fiord abundance estimates were corrected for whales that were too deep to be identified in the images. The estimates were significantly lower in 2021 (197 whales, 95%CI: 180-216) and 2022 (194 whales, 95%CI: 172-218) compared to 2020 (393 whales, 95%CI: 366-422). Other fiords were only imaged in 2021 and 2022, resulting in average corrected abundance estimates for all fiords of 462 (95% CI: 425-502) and 252 (95%CI: 226-280) beluga whales, respectively. Downsampling of 30 cm images to 50 cm resulted in up to 45% fewer whales detected. The only critical habitat identified within the summer distribution was in Clearwater Fiord, in or near the estuary freshwater plume and in a bay to the west of the plume. The identified critical habitats should be areas of consideration in the continued discussion on the protection and sustainability of the Cumberland Sound beluga whale population. [ABSTRACT FROM AUTHOR]

We examined the reproductive behavior (courtship and mating), seasonality and its distribution in three Mobula species, spinetail, bentfin, and Munk's devil rays (M. mobular, M. thurstoni, and M. munkiana) in the southwestern Gulf of California, Mexico, using boat surveys (with drone and in-water observations) (n = 69 survey days), spotter planes (n = 428 flights), and citizen science observations (n = 31). We examined whether (1) reproductive grounds existed within the area for any of these species, (2) whether reproductive behavior followed seasonal patterns, and (3) if this behavior was similar among all mobula rays. We observed reproductive behavior in 221 events in 2017 and 2021–2022, for M. mobular (n = 10), M. thurstoni (n = 3), and M. munkiana (n = 208) dispersed along 312 km of the eastern Baja California Peninsula between 4 m and 6.3 km away from the coast. Most events (n = 209) occurred in the La Ventana and Ensenada de Muertos areas. Courtship was observed for M. mobular and M. thurstoni and a copulation attempt for M. munkiana, with reproductive behavior following a seasonal pattern occurring from March to August, with a peak during May (81.9% of the events). Mobula munkiana displayed previously undescribed behaviors, such as the "piggyback leaps" as a pre-copulatory position and the "courtship vortex", where 122 individuals were observed circling in a clockwise direction for 5 h with courtship groups joining and leaving the main vortex formation. This study highlights the areas of La Ventana and Ensenada de Muertos as critical habitats for reproductive behavior of two endangered and one vulnerable devil ray species. [ABSTRACT FROM AUTHOR]

Understanding habitat requirements for species at risk is crucial for effective conservation management, even though the location and extent of vital habitats may be unknown for rare or elusive species.In the case of marine species, determining important habitat often relies on limited occurrence data or extrapolation from species distribution models (SDMs). SDMs predict habitat by associating species records with environmental variables, assuming a functional ecological relationship.This study focuses on northern bottlenose whales (NBW; Hyperoodon ampullatus) and Sowerby's beaked whales (SBW; Mesoplodon bidens) in the western North Atlantic. As both NBW and SBW are at risk in Canada, the objective was to identify the extent and function of important habitats to guide conservation efforts.The analysis mapped all available geographic occurrence data and used passive acoustic monitoring (PAM) data to inform the development of ensemble SDMs to predict potential habitat and assess the persistence of realized habitat use.Important habitats for NBW and SBW were found primarily concentrated along the continental shelf edges, at an average depth of 1200 m ± 460 SD. All habitat areas support foraging and movement and critical life history functions for both species.The Gully and other submarine canyons off eastern Nova Scotia emerged as important areas for both species, validating the existing Critical Habitat for NBW. However, spatial–temporal patterns diverged on either side of this region. North‐eastern Newfoundland was identified as the next closest area of near‐year‐round presence for NBW, whereas the south‐western Scotian Shelf region, Georges Bank and the Fundian Channel supported persistent foraging by SBW.By integrating multiple data sources (sightings, acoustic detections and SDMs) and demonstrating the temporal persistence of habitat use by NBW and SBW, this study provides valuable insights for identifying, protecting and managing important habitat for beaked whales. [ABSTRACT FROM AUTHOR]

Habitat descriptions found in critical habitat designations and recovery plans are important for protecting endangered species. However, in order to protect critical habitat, it is necessary to update descriptions of habitat use when range shifts occur or new studies change the understanding of habitat use.This study examined the habitat use of a threatened desert fish to determine whether current habitat use matched the descriptions in recovery documents. Recovery documents describe humpback chub (Gila cypha) as being dependent on rocky, canyon‐bound habitats during all life stages, but recent surveys found humpback chub in open, silt‐laden habitats, suggesting this species may be able to occupy a wider range of habitats.Hoop net catch data from a long‐term monitoring project in the Colorado River were used to compare catches of two size classes: juvenile/subadult (<200 mm total length [TL]) and adult humpback chub (≥200 mm TL). Catch information was analysed on an individual net scale and on a geological segment scale using generalized linear mixed models.There was no difference in juvenile/subadult humpback chub catch between hoop nets set in rocky habitat compared with habitat with only fine sediment. Humpback chub catch for all life stages in a river segment characterized by silt banks exceeded or was not significantly different from catch in rocky segments.This case study demonstrates the importance of revisiting habitat descriptions, sampling in areas outside known or expected habitat and incorporating new data related to range expansion or habitat changes in recovery strategies to better describe and protect habitats that can support imperilled species. [ABSTRACT FROM AUTHOR]

Seagrasses are globally acknowledged as crucial habitats as they provide a variety of ecosystem services. Mexico’s legislation protects most of these marine plants; however, the protection often fails in application. The Gulf of California, despite being a biodiversity hotspot, has scant data on seagrasses. Here, human activity and climate change increasingly threaten these coastal ecosystems, with conservation and research efforts lacking coordination at a regional level. Our manuscript aimed to review and standardize existing data on Gulf of California seagrass species, ensuring open access for data updates; pinpointing conservation deficiencies; and guiding future research. We have added new records to the official public data, but we were able to recapture only 25% of the seagrass locations meaning a potential reduction in their historical distribution of 45.8%. Even though Mexico’s legislation protects some species of seagrasses, it protection often fails in the application. We identified that only 6.1% of the seagrass locations are within protected areas that recognize their presence in their management plans (e.g., the Balandra Flora and Fauna Protected Area and the Upper Gulf of California and Colorado River Delta Biosphere Reserve). At least 55.9% of seagrass records are associated with potentially damaging activities like pollution, coastal modification or biological resources use, while 23% are exposed to higher frequency of marine heatwaves. Given the importance of seagrass meadows under Mexican law and their internationally recognized ecological value, sharing current information and guiding research is essential. Our study seeks to galvanize renewed research initiatives and raise more awareness on the conservation of the Gulf of California’s seagrasses.

Abstract: In California (USA), seasonal lagoons provide important oversummer rearing habitat for juvenile steelhead trout (anadromous Oncorhynchus mykiss). However, key water quality parameters such as temperature and dissolved oxygen concentration can periodically approach or exceed the physiological tolerances of steelhead during the protracted dry season. A field study employing distributed temperature sensing technology, water quality monitoring, habitat mapping, and mark-recapture sampling was conducted to examine how shifting environmental conditions affected the performance and behavior of juvenile steelhead in the Scott Creek estuary/lagoon (Santa Cruz County). Abiotic conditions were driven by episodic inputs of seawater to the typically freshwater lagoon. During midsummer, the water column was vertically stratified which reduced suitable lagoon rearing habitat by approximately 40%. Nevertheless, steelhead abundance, growth, and condition factor were high during the summer and decreased in autumn following lagoon destratification and cooling. Unlike previous work, this study identified limited emigration from the lagoon to riverine habitat during the summer. Instead, juvenile steelhead exhibited crepuscular movement patterns within the lagoon, with peaks in upstream (to upper lagoon habitat) and downstream (to lower lagoon habitat) movement occurring at dawn and dusk, respectively. This study underscores that habitat complexity and connectivity are critical for juvenile steelhead production and persistence and provides insight into steelhead habitat use and behavior in seasonal lagoons.

The Ramaroshan Lake Complex, situated in the mid-hills of Sudurpaschim Province, is renowned for its scenic beauty, yet there is a notable dearth of information regarding its biodiversity and ecological status. This study represents the first systematic examination of seasonal variations in water quality parameters and biodiversity encompassing aquatic macroinvertebrates, fishes, birds, herpetofauna, mammals, and macrophytes, as well as the surrounding vegetation within the complex, spanning the winters and summers of 2018 and 2019. Among the twenty water quality parameters investigated, thirteen displayed significant seasonal differences across the lakes (p <0.05), with Batula and Ramaroshan lakes exhibiting elevated nutrient levels. Lamadaya Lake stood out with a highly diverse macroinvertebrate community compared to other lakes, while overall, the study recorded 45 aquatic macroinvertebrate families, three fish species, 79 bird species, 12 herpetofauna species, 12 mammal species, and 26 macrophyte species within the complex. Additionally, the surrounding vegetation comprised 193 distinct plant species. Notably, the complex currently hosts 14 IUCN Red List species, including Near Threatened (5), Vulnerable (5), Critically Endangered (1), and Endangered (3) species, as well as five migratory wetland bird species, underscoring its significance for wildlife conservation. Given the diverse and cross-cutting nature of wetlands, the development of sciencebased policies and coordinated efforts among central, provincial, and local governments are essential for the preservation and sustainable management of these vital ecosystems. [ABSTRACT FROM AUTHOR]

Least Flycatchers (Empidonax minimus), like most aerial insectivores, have declined rapidly over the last 50 years in North America, mostly due to the extensive use of insecticides. Since the Least Flycatcher is the most common bird encountered in the Beaverhill Natural Area, located in central Alberta, Canada, likely due to high insect densities, we studied the nesting success and habitat use of this species in the summer of 2022. We monitored 28 nests until fledging and found a high nest success rate and more nesting in trembling aspen trees (Populus tremuloides), compared to balsam poplar trees (Populus balsamifera). We found that mean host tree height was greater for successful nests than unsuccessful nests. In addition, based on a breeding bird census, we found a high breeding density in our research area. Understanding the relationship between breeding success and habitat is important for conservation actions to be effective in the future. Our results show that the Beaverhill Natural Area has high-quality habitat for Least Flycatchers and is a candidate for critical habitat when designated under the Canadian Species at Risk Act. El mosquero Empidonax minimus, como la mayoría de insectívoros aéreos, han declinado rápidamente en los últimos 50 años en Norteamérica, mayormente debido al uso extensivo de pesticidas. Puesto que el mosquero Empidonax minimus es el ave más común encontrada en el Área Natural Beaverhill, localizada en Alberta central, Canadá, posiblemente debido a altas densidades de insectos, estudiamos el éxito de anidamiento y el uso de hábitat de esta especie en el verano de 2022. Monitoreamos 28 nidos hasta su emancipación y encontramos una alta tasa de éxito de nido y más anidamiento en álamo temblón (Populus tremuloides), comparado con álamo balsámico (Populus balsamifera). Encontramos que el promedio de altura del árbol hospedero era superior para nidos exitosos que para nidos no exitosos. Además, basados en censo de aves reproductivas, encontramos una alta densidad reproductiva en nuestra área de investigación. Entender la relación entre el éxito reproductivo y el hábitat es importante para que las acciones de conservación sean efectivas en el futuro. Nuestros resultados muestran que el Área Natural Beaverhill es un hábitat de alta calidad para el mosquero Empidonax minimus y es candidata para ser designada como hábitat crítico bajo el Acta de Riesgo de Especies Canadienses. Palabras clave: éxito de anidamiento, hábitat crítico, hábitar de nido, insectiacutívoro aéreo, productividad. [ABSTRACT FROM AUTHOR]

Endangered in Canada and the United States, the Poweshiek skipperling's (Oarisma poweshiek (Parker) (Lepidoptera: Hesperiidae)) recovery likely depends on understanding more about its ecology. The characteristics of locations which facilitate various adult activities, such as oviposition and resting, in Manitoba tall grass prairie are unknown. We followed adults in prairie patches to identify locations associated with various behaviours, and subsequently measure vegetative, structural and microclimatic attributes at these microhabitats. Adult skipperlings were observed 34 times resulting in 24 flight tracks and 56 point interactions being recorded. Skipperlings flew almost exclusively in the prairie plant community, with few flights into wetter communities and none in forests. Tracks tended to be tortuous, typical of occupancy in higher-quality habitats. Adult activities appeared to be distributed along a soil moisture gradient: oviposition was associated with the relatively mesic section, resting and/or basking with the drier section, and nectar feeding generally associated with sections throughout the gradient. Adults nectared from a mixture of species during the flight period, consuming nectar from Rudbeckia hirta Linnaeus (Asteraceae) most often. We report previously unknown aspects of O. poweshiek's ecology. Implications for conservation: Our findings describe how adult skipperlings might use sections of prairie with different soil moistures to lay eggs, rest, bask and consume nectar. We visualise approaches to ensure all sections are disturbed during stewardship activities and evaluate the degree to which all facilitative soil moistures are present in candidate (re)introduction sites, for the successful recovery of O. poweshiek. [ABSTRACT FROM AUTHOR]

Abstract The persistence of threatened wildlife species depends on successful conservation and restoration of habitats, but climate change and other stressors make these tasks increasingly challenging. Applying climate change vulnerability analyses to contemporary wildlife management can be difficult because most analyses predict direct effects of future climate on wildlife species at broad geographic scales, rather than assessing their habitats at local scales (

Limiting disturbance in critical habitats is an important part of ensuring the well-being and sustainability of populations at risk, such as Cumberland Sound beluga whales (Delphinapterus leucas). Using non-disruptive Very High Resolution (VHR) satellite imagery, an emerging tool in cetacean monitoring, we aimed to estimate summer abundance and identify critical habitat for Cumberland Sound beluga whales. Specifically we looked in fiords that comprise their summer distribution, such as Clearwater Fiord where there is a large estuary, an important habitat to many beluga populations. Satellite images of the area were collected in 2020 and 2021, at 30 cm resolution, and in 2022 at 50 cm resolution. We evaluated beluga whale distribution using Kernel density, and identified critical habitats as areas consistently part of the beluga whale core distribution across years. Clearwater Fiord abundance estimates were corrected for whales that were too deep to be identified in the images. The estimates were significantly lower in 2021 (197 whales, 95%CI: 180-216) and 2022 (194 whales, 95%CI: 172-218) compared to 2020 (393 whales, 95%CI: 366-422). Other fiords were only imaged in 2021 and 2022, resulting in average corrected abundance estimates for all fiords of 462 (95% CI: 425-502) and 252 (95%CI: 226-280) beluga whales, respectively. Downsampling of 30 cm images to 50 cm resulted in up to 45% fewer whales detected. The only critical habitat identified within the summer distribution was in Clearwater Fiord, in or near the estuary freshwater plume and in a bay to the west of the plume. The identified critical habitats should be areas of consideration in the continued discussion on the protection and sustainability of the Cumberland Sound beluga whale population.

Wetlands are among the most important habitats of highly wetland-dependent waterbirds but are subject to ongoing habitat loss and degradation owing to intensified anthropogenic activities. The scarcity of human and natural resources makes effective habitat protection an important concern. Here, we aimed to investigate waterbird habitat protection methods for Anhui Province, China, a critical stopover and wintering area on the East Asian-Australasian Flyway that features rich wetland resources subject to significant habitat loss and degradation. We evaluated the status and importance of 306 wintering waterbird habitats and identified the key environmental influences and current protection gaps using the entropy weights method and generalized additive modeling. We found 73 important habitats for waterbirds in Anhui Province, which were classified into levels of importance (descending from I to V) according to the natural discontinuity method. Level I and Level II habitats were mainly located in the Yangtze River floodplain and Level IV habitats in the Huaihe River floodplain. The gap analysis showed that 42 important waterbird habitats had protection gaps, accounting for 57.53% of the total area. Waterbird habitat importance was significantly correlated with elevation, normalized vegetation index, lake area, and lake circumference but not with distance from roads or population density. The results of this study provide scientific information for waterbird habitat conservation planning, which is crucial for maintaining wetland ecosystem functions.

Most research on boreal populations of woodland caribou (Rangifer tarandus caribou) has been conducted in areas of high anthropogenic disturbance. However, a large portion of the species' range overlaps relatively pristine areas primarily affected by natural disturbances, such as wildfire. Climate‐driven habitat change is a key concern for the conservation of boreal‐dependent species, where management decisions have yet to consider knowledge from multiple ecological domains integrated into a cohesive and spatially explicit forecast of species‐specific habitat and demography. We used a novel ecological forecasting framework to provide climate‐sensitive projections of habitat and demography for five boreal caribou monitoring areas within the Northwest Territories (NWT), Canada, over 90 years. Importantly, we quantify uncertainty around forecasted mean values. Our results suggest habitat suitability may increase in central and southwest regions of the NWT's Taiga Plains ecozone but decrease in southern and northwestern regions driven by conversion of coniferous to deciduous forests. We do not project that boreal caribou population growth rates will change despite forecasted changes to habitat suitability. Our results emphasize the importance of efforts to protect and restore northern boreal caribou habitat despite climate uncertainty while highlighting expected spatial variations that are important considerations for local people who rely on them. An ability to reproduce previous work, and critical thought when incorporating sources of uncertainty, will be important to refine forecasts, derive management decisions, and improve conservation efficacy for northern species at risk. [ABSTRACT FROM AUTHOR]

Pine rockland habitat of South Florida is among the most highly threatened terrestrial ecosystems in the neo-subtropics and is among the rarest worldwide. With only 1.2% of its original extent remaining outside Everglades National Park, fewer than 780 hectares of this ecosystem remains across all of South Florida. This fire-dependent ecosystem—habitat for many rare, endemic species—has experienced substantial deforestation and defaunation due to urbanization, land use change, habitat fragmentation, fire suppression, and exotic plant invasions. Owing to the small size of remaining fragments, and the fact that most are surrounded by urbanization, adequate burning regimes are suppressed. The Richmond Tract, a complex of twelve separate parcels under multiple private and public ownership partially surrounding Zoo Miami, is the largest tract of pine rockland outside the federal protection of Everglades National Park. In this article, we take inventory of the threatened biodiversity at the Richmond Tract and focus on the policy and management landscape. We take a close look at threats to the pine rockland's persistence here and review approaches that either help maintain the health of this ecosystem or those that may need to be reconsidered. We end by discussing coordination among multiple stakeholder groups, the potential use for incentive-based conservation practices, and suggesting ways to improve management in highly urbanized South Florida. [ABSTRACT FROM AUTHOR]

Globally, Marine Protected Areas are an important tool in the conservation of large marine vertebrates. Recent studies have highlighted the use of protected areas by imperiled green turtles (Chelonia mydas) in the southern Gulf of Mexico. To identify and characterize inter-nesting, migratory, and foraging areas for green turtles that nest in the northern Gulf of Mexico, we deployed 14 satellite tags on 13 individual green turtles after nesting in Northwest Florida. We used switching state-space modeling to highlight turtle use in the Florida Keys National Marine Sanctuary and in habitat outside of protected areas such as near Cape Sable, Florida and off the Yucatán Peninsula, Mexico. Turtles were tracked for 21–217 days and migrated for a mean of 22 days. Five individuals used stopover sites during migration; these sites were in areas of dense seagrass habitat, often within boundaries of existing Aquatic Preserves. Turtles established mean foraging home ranges of 118.0 km2 (50% kernel density estimate) with foraging centroids that were 0.33–7.3 km apart. The area off Cape Sable, Florida, which lies outside of currently protected area boundaries, appears to be a hotspot for green turtles that nest throughout the Gulf of Mexico. While protected areas in the Gulf of Mexico are used by this subset of nesting green turtles, several key sites remain unprotected. These findings are relevant when considering expansion of currently protected areas and in defining critical habitat for this species.

The northeastern Pacific northern and southern resident killer whale (Orcinus orca) populations are listed as threatened and endangered in Canada, respectively, with persistent, bioaccumulative contaminants, such as polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), posing threats to their recovery. Concentrations of PCBs and PBDEs in subtidal surface sediments collected from 97 sites along the British Columbia (BC) coast were used to identify their distribution and profiles, and to assess killer whale habitat quality. Victoria Harbour (VH3(site ID: 1)) sediments exhibited the highest PCB and PBDE concentrations. For PCBs, PCB‐138 was found at the highest concentration, followed by PCB‐153, PCB‐110, PCB‐149, PCB‐101, and PCB‐118. For PBDEs, individual congeners were ranked as follows: BDE‐209 > BDE‐207 > BDE‐206 > BDE‐208 > BDE‐47 > BDE‐99. Principal component analyses (PCA) illustrated the variations in contaminant profiles, with PC1 for PCBs and PBDEs correlated with the octanol‐water partition coefficient (log KOW, p < 0.003). Based on the PCA, sediment particle size, total organic carbon (TOC), and water depth at collection were other factors associated with the distribution of PBDEs, while PCB profiles were associated with TOC. Total PCB and PBDE concentrations at 100% and 34% of the sites, respectively, exceeded the recently adopted British Columbia's Ministry of Environment and Climate Change Strategy Working Sediment Quality Guidelines (PCBs 3.7 pg/g dry wt and PBDEs 1000 pg/g dry wt), considered protective of killer whales. Our findings suggest that the legacy of banned PCBs and PBDEs has the potential to constrain the recovery of killer whales as a result of their mobilization from sediments and consequent uptake by marine food webs. Environ Toxicol Chem 2022;41:2139–2151. © 2022 SETAC [ABSTRACT FROM AUTHOR]

Cetacean species are highly mobile, most of them regularly travelling over long distances, thereby presenting complex obstacles to their conservation. Identification of their critical habitats, specifically those parts of a cetacean's range that are essential for day‐to‐day survival and for maintaining a healthy population growth rate, is necessary for their effective protection.This study presents a summary of the data on cetacean sightings during surveys that covered substantial parts of the Russian Far East coastal waters from the Okhotsk Sea to Chukotka in order to determine important areas for particular cetacean species. Sixteen cetacean species were registered during the surveys, and for 12 of them with sufficient numbers of sightings, zones with maximum sighting rates were identified.Only 13% of all cetacean sightings and 22% of sightings of protected species occurred within marine protected areas (MPAs). The highest sighting rates for protected species were concentrated off north‐eastern Sakhalin Island, in the Shantar Area, in Anadyr Gulf, in Kresta Bay and in the waters off eastern Chukotka. The analysis of the distribution patterns of various cetacean species in Russian Far East seas provides a solid base for future conservation planning. Lack of specific MPAs for protection of cetaceans and associated biodiversity hinders marine conservation in Russian Far East seas.The study highlights the specific zones important for various cetacean species and suggests the extension of some existing MPAs and the creation of new MPAs for future spatial habitat protection measures. [ABSTRACT FROM AUTHOR]

Deciding when to protect threatened species habitat when complete knowledge about the habitat extent is uncertain is a common problem in conservation. More accurate habitat mapping improves conservation outcomes once that habitat is protected. However, delaying protection to improve accuracy can lead to species decline or, at worst, local extinction when threats to that habitat continue unabated before protection is implemented. Hence, there is a trade‐off between gaining knowledge and taking conservation action.We quantified this trade‐off and determined the optimal time to spend learning about a species' habitat before protecting that habitat. We used a range of hypothetical learning curves to model improvements in the accuracy of predicted habitat over time, and receiver operating characteristic (ROC) curves to model the corresponding increase in the proportion of habitat protected. We used rates of habitat loss to model the impact of delaying habitat protection and derived analytical solutions to the problem for different types of learning curves.We illustrate our approach using two threatened species, the koala Phascolarctos cinereus in Australia and northern abalone Haliotis kamtschatkana in Canada. Our approach confirms that when impacts of threatening processes are incurred rapidly, the need for timely protection is high, and the optimal time to spend learning is short for all learning curves. When the rate of habitat loss is low, we benefit from better habitat identification, and the optimal time to protect is sensitive to assumptions about how we learn and the proportion of non‐habitat we are willing to protect unnecessarily.Navigating the trade‐off between information gain and timely action is a common problem in conservation. By optimizing the trade‐off between the benefits of improving mapping accuracy and the costs of delaying protection, we provide guidelines on the effective allocation of resources between habitat identification and habitat protection. Importantly, by explicitly modelling this trade‐off with a range of learning curves and estimates of the rates of habitat loss or other threatening processes, we can predict the optimal time to spend learning even when relatively little is known about a species and its habitat. [ABSTRACT FROM AUTHOR]

The Hawaiian archipelago was formerly home to one of the most species-rich land snail faunas (> 752 species), with levels of endemism > 99%. Many native Hawaiian land snail species are now extinct, and the remaining fauna is vulnerable. Unfortunately, lack of information on critical habitat requirements for Hawaiian land snails limits the development of effective conservation strategies. The purpose of this study was to examine the plant host preferences of native arboreal land snails in Puʻu Kukui Watershed, West Maui, Hawaiʻi, and compare these patterns to those from similar studies on the islands of Oʻahu and Hawaiʻi. Concordant with studies on other islands, we found that four species from three diverse families of snails in Puʻu Kukui Watershed had preferences for a few species of understorey plants. These were not the most abundant canopy or mid canopy species, indicating that forests without key understorey plants may not support the few remaining lineages of native snails. Preference for Broussaisia arguta among various island endemic snails across all studies indicates that this species is important for restoration to improve snail habitat. As studies examining host plant preferences are often incongruent with studies examining snail feeding, we suggest that we are in the infancy of defining what constitutes critical habitat for most Hawaiian arboreal snails. However, our results indicate that preserving diverse native plant assemblages, particularly understorey plant species, which facilitate key interactions, is critical to the goal of conserving the remaining threatened snail fauna. [ABSTRACT FROM AUTHOR]

The Endangered Species Act (ESA) requires that areas be designated as critical habitat for species that are protected under the Act. Once designated, critical habitat is protected from “destruction or adverse modification” by Section 7(a)(2) of the ESA, which applies to any action authorized, funded, or carried out by a federal agency, including permits and other authorizations issued to private landowners and resource users. In 1978, Congress enacted extensive amendments to the ESA that were intended to limit the scope of critical habitat to areas essential for the survival of protected species. Based on these amendments, the U.S. Fish and Wildlife Service and the National Marine Fisheries Service adopted regulations that recognized critical habitat’s limited role in conserving species, including a definition of “destruction or adverse modification” that emphasized impacts to the protected species’ survival. In Sierra Club v. U.S. Fish and Wildlife Service and Gifford Pinchot Task Force v. U.S. Fish and Wildlife Service however, the Fifth Circuit and the Ninth Circuit respectively held that the agencies’ adverse modification definition is unlawful and that the purpose of critical habitat is to recover species. These cases have strongly influenced the administration of the ESA over the past decade and the Services recently relied on these cases to justify regulations that will transform critical habitat into recovery habitat. The authors maintain that a reassessment of the role of critical habitat is needed to ensure that the regulatory and judicial treatment of critical habitat conforms to the intent of Congress.

Decision makers often cite data quality as a limitation in environmental management. Value of information approaches evaluate the benefit of new data collection for management outcomes. Pesticide exposure risk assessment for endangered species is one context where data limitations may affect decisions and a value of information type approach could be useful for identifying optimal data quality and resolution. Under the U.S. Federal Insecticide, Fungicide and Rodenticide Act, the U.S. Environmental Protection Agency (EPA) is responsible for registering pesticides before they can be sold and regularly reviewing pesticides. Section 7 of the Endangered Species Act requires that the EPA consider potential impacts of pesticides to listed endangered species and critical habitats in this process, and for the Services—U.S. Fish and Wildlife Service and National Marine Fisheries Service—to complete a formal Section 7 consultation if the EPA deems it necessary. The current process is time‐intensive, lacks transparency and confidence among stakeholders, and leaves hundreds of unreviewed pesticides on the market. Increasing the resolution of pesticide usage data could address these concerns by improving estimated overlaps between species ranges and pesticide usage. Thus, we evaluated the relative importance of different resolutions of pesticide usage data for assessing expected carbaryl exposure to endangered plant species endemic to California. We found that spatially explicit, township resolution usage data (~36 mile2) excluded 33% of terrestrial plants (55/168) and 51% their critical habitats (27/53) from requiring a Section 7 consultation, while coarser resolution data excluded none. In contrast, the EPA's biological evaluation for carbaryl only excludes 4% of terrestrial plants (nationally) from requiring formal Section 7 consultation. This suggests high‐resolution data could increase pesticide review efficiency and decrease the amount of time pesticides remain on the market without a formal evaluation. [ABSTRACT FROM AUTHOR]

We applied spatial distribution and reserve selection modeling to identify critical habitat network for 50 critically endangered plant species of Uzbekistan. We created maps of relative habitat suitability, converted them into maps of species critical habitat, and the latter served as input to the spatial conservation prioritization program Zonation. Although all studied species were extremely rare, the extent of their predicted critical habitat ranged from 2.6 to 15,508 km2 and did not correlate with the number of occurrence records. It appears that the extent of the threatened species predicted suitable area is an indicator of whether the species rarity is inherent due to vary narrow ecological niche or caused solely by anthropogenic activity. This has important conservation implications. Imperiled species from the first category are less amenable (if at all) to such conservation actions as trans- or relocation (i.e. there is no alternative to protecting the last remaining populations). Species from the second group can potentially grow in many more locations than they currently occupy, and therefore, for these species, translocation can be the most appropriate strategy when their last remaining locations are degraded or can not be protected for whatever reason. Based on results of nature reserve design that utilized SDM-predicted maps for 50 imperiled species, we recommend adding new areas to the existing network of protected areas to cover critical habitats of highly threatened plant species. The highest priority for adding have the territories harboring critical habitat of disproportionally high number of imperiled species, and we found that they all are concentrated in the eastern part of Uzbekistan. [ABSTRACT FROM AUTHOR]

Abstract Decision makers often cite data quality as a limitation in environmental management. Value of information approaches evaluate the benefit of new data collection for management outcomes. Pesticide exposure risk assessment for endangered species is one context where data limitations may affect decisions and a value of information type approach could be useful for identifying optimal data quality and resolution. Under the U.S. Federal Insecticide, Fungicide and Rodenticide Act, the U.S. Environmental Protection Agency (EPA) is responsible for registering pesticides before they can be sold and regularly reviewing pesticides. Section 7 of the Endangered Species Act requires that the EPA consider potential impacts of pesticides to listed endangered species and critical habitats in this process, and for the Services—U.S. Fish and Wildlife Service and National Marine Fisheries Service—to complete a formal Section 7 consultation if the EPA deems it necessary. The current process is time‐intensive, lacks transparency and confidence among stakeholders, and leaves hundreds of unreviewed pesticides on the market. Increasing the resolution of pesticide usage data could address these concerns by improving estimated overlaps between species ranges and pesticide usage. Thus, we evaluated the relative importance of different resolutions of pesticide usage data for assessing expected carbaryl exposure to endangered plant species endemic to California. We found that spatially explicit, township resolution usage data (~36 mile2) excluded 33% of terrestrial plants (55/168) and 51% their critical habitats (27/53) from requiring a Section 7 consultation, while coarser resolution data excluded none. In contrast, the EPA's biological evaluation for carbaryl only excludes 4% of terrestrial plants (nationally) from requiring formal Section 7 consultation. This suggests high‐resolution data could increase pesticide review efficiency and decrease the amount of time pesticides remain on the market without a formal evaluation.

The inland waters around southern Vancouver Island and northern Washington State, known as the Salish Sea, host critical habitat for endangered southern resident killer whales (SRKW). This is, however, a highly traversed area, with approaches to industrial ports and coastal cities, international shipping lanes, ferry routes, and considerable recreational vessel traffic. Vessel noise is a key threat to SRKW prosperity, and so conservation measures directed to mitigate its effects have been explored annually since 2017. Here, we describe trials undertaken in 2020, which included spatially limited slowdown zones, exclusion areas as Interim whale Sanctuary Zones (ISZs), and a lateral displacement of tug transits to increase the distance between their route and SRKW foraging areas. To assess each of the measures we first considered the level of mariner participation using data from the Automated Identification Systems (AIS), mandatory for commercial vessels. Knowing this, the changes in soundscape were examined, focused on impacts on broadband (10 Hz to 100 kHz) ambient noise and the frequencies used by SRKW for communication (500 Hz to 15 kHz) and echolocation (15 to 100 kHz). A control period of two-months prior to trial initiation was used to quantify the changes. High levels (> 80%) of compliance were found for each measure, except ISZs, where observance was low. Median reduction in speeds ranged from 0.2–3.5 knots. Resulting sound reductions were most notable in the lower frequencies, although reductions were also recorded in SRKW pertinent ranges. Tug displacement also reduced ambient noise in these frequencies, despite making up a small portion of the overall traffic. The management trials were effective in reducing potential impacts singularly and in concert. Greater awareness and stakeholder engagement may increase compliance and, therefore, the efficacy of measures in the future.

1.Cook Inlet beluga whales (CIBWs; Delphinapterus leucas), are an isolated and declining endangered population in Alaska, USA. Their critical habitat has been broadly defined, with little empirical data on habitat use to direct management actions. This article examines data collected during surveys for a long‐term photo‐ID study to gain insight into the use of critical habitat by CIBW groups and individuals, with a focus on areas where belugas were observed feeding, calving, rearing young, and in transit. It also describes patterns of group distribution, size, and composition, according to sex and age class, in order to better understand how CIBWs are distributed throughout critical habitat during the ice‐free season. The results are presented according to survey month and survey zone, so that patterns of habitat use are accessible in a useful format to aid managers in evaluations of how timing and location of human activities occurring in CIBW critical habitat may overlap with CIBW occurrence and use of these areas.2.There were 575 beluga groups encountered during 477 photo‐ID surveys conducted in CIBW critical habitat 2005–2017. CIBW locations were mapped, and models were developed to test for temporal and spatial patterns. Approximately 400 individual whales were identified, and their sighting histories were compiled to examine residency and movement patterns.3.CIBWs were found seasonally in distinct areas, where they aggregate in large groups of both sexes and all age classes while rearing calves and feeding. These areas, and the general corridors connecting them, represent important beluga habitat that warrant focused management attention and protection efforts.4.Whales travelling among distinct areas of Cook Inlet increase their likelihood of exposure to multiple, localized threats.5.Habitat protection and the regulation of anthropogenic activities should consider cumulative effects of all activities in the range of CIBWs and their potential to affect the entire population. [ABSTRACT FROM AUTHOR]

Abstract Identifying habitat that is essential to the recovery of species at risk, known as critical habitat, is a major focus of species at risk legislation, yet there has been little research on the degree to which these areas are protected. Here, we first review the provisions for protecting critical habitat on non‐federal lands within Canada's Species at Risk Act (SARA). Next, we use the declining southern mountain population of woodland caribou (Rangifer tarandus caribou) in British Columbia, Canada as a case study to show that identification of critical habitat does not guarantee its protection on non‐federal lands. Our analyses show that 909 km2 of critical habitat identified on provincial lands were logged in 5 years after it was legally identified under SARA. Existing provincial legislation and policies have provided incomplete protection of caribou critical habitat, and Canada's federal government has yet to exercise authority under SARA that could protect these areas. In the absence of nondiscretionary protection under provincial legislation, a combination of alternative mechanisms, involving all levels of government, Indigenous people, and industry, will be essential to protect critical habitat and help recover species at risk.

Compared with our understanding of most aspects of sea turtle biology, knowledge of the surface-pelagic juvenile life stages remains limited. Young North Atlantic cheloniids (hard-shelled sea turtles) are closely associated with surface-pelagic drift communities (SPDCs), which are dominated by macroalgae of the genus Sargassum. We quantified SPDCs in the eastern Gulf of Mexico, a region that hosts four species of cheloniids during their surface-pelagic juvenile stage. Landsat satellite imagery was used to identify and measure the areal coverage of SPDCs in the eastern Gulf during 2003-2011 (1323 images). Although the SPDC coverage varied annually, seasonally, and spatially, SPDCs were present year-round, with an estimated mean area of SPDC in each Landsat image of 4.9 km2 (SD = 10.1). The area of SPDCs observed was inversely proportional to sea-surface wind velocity (Spearman's r = -0.33, p

Boreal forests provide numerous ecological services, including the ability to store large amounts of carbon, and are of significance to global biodiversity. Increases in industrial activities in boreal landscapes since the mid‐20th century have added to concerns over biodiversity loss and climate change. Boreal forests are home to dwindling populations of boreal caribou Rangifer tarandus caribou in Canada, a species at risk that requires large, undisturbed landscapes for persistence. In 2012, the Canadian government defined critical habitat for boreal caribou by relating calf recruitment to disturbances. Some have questioned whether the recruitment relationship can be extrapolated beyond the environmental conditions represented in the analysis.We examined the effects of human disturbances and fire (alone and in combination) on variation in recruitment and adult female survival using data from 58 study areas in Canada. Top models were used in aspatial scenarios of landscape change to evaluate the efficacy of the critical habitat definition in achieving the recovery objectives for boreal caribou in two contrasting landscapes: Little Smoky, dominated by high levels of human disturbances, and the northern boreal shield of Saskatchewan (SK1), dominated by fire.The top recruitment model suggested the negative effect of fire was three to four times smaller than human disturbances. The top adult female survival model included human disturbances only. These results re‐affirm that human disturbances are the primary factor contributing to boreal caribou declines.Our aspatial scenarios suggested that undisturbed habitat would have to increase to ≥68% for Little Smoky to maintain a self‐sustaining population of boreal caribou with some degree of certainty. In contrast, the SK1 population was self‐sustaining with 40% undisturbed habitat when fire disturbance predominates, but could become vulnerable with increases in human disturbances (8%–9%).Policy implications. Boreal caribou are listed as threatened under Canada's Species at Risk Act. Our results suggest that the 65% undisturbed critical habitat designation in Canada's boreal caribou Recovery Strategy may serve as a reasonable proxy for achieving self‐sustaining populations of boreal caribou in landscapes dominated by human disturbances. However, some populations may be less or more vulnerable, as illustrated by the scenarios in a landscape dominated by fire (SK1). Continued population monitoring will be essential to assessing the effectiveness of land management strategies developed for boreal caribou recovery, especially with climate change. [ABSTRACT FROM AUTHOR]

Aim: We conduct a biogeographical assessment of orchids in a global biodiversity hotspot to explore their distribution and occurrences of local hotspots while identifying geographic attributes underpinning diversity patterns. We evaluate habitat characteristics associated with orchid diversity hotspots and make comparisons to other centres of orchid diversity to test for global trends. The ultimate goal was to identify an overall set of parameters that effectively characterize critical habitats to target in local and global orchid conservation efforts. Location: Costa Rica; Mesoamerica. Taxon: Orchidaceae. Methods: Data from an extensive set of herbarium records were used to map orchid distributions and to identify diversity hotspots. Hotspot data were combined with geographic attribute data, including environmental and geopolitical variables, and a random forest regression model was utilized to assess the importance of each variable for explaining the distribution of orchid hotspots. A likelihood model was created based on variable importance to identify locations where suitable habitats and unidentified orchid hotspots might occur. Results: Orchids were widely distributed and hotspots occurred primarily in mountainous regions, but occasionally at lower elevations. Precipitation and vegetation cover were the most important predictive variables associated with orchid hotspots. Variable values underpinning Costa Rican orchid hotspots were similar to those reported at other sites worldwide. Models also identified suitable habitats for sustaining orchid diversity that occurred outside of known hotspots and protected areas. Main conclusions: Several orchid diversity hotspots and potentially suitable habitats occur outside of known distributions and/or protected areas. Recognition of these sites and their associated geographic attributes provides clear targets for optimizing orchid conservation efforts in Costa Rica, although certain caveats warrant consideration. Habitats linked with orchid hotspots in Costa Rica were similar to those documented elsewhere, suggesting the existence of a common biogeographical trend regarding critical habitats for orchid conservation in disparate tropical regions. [ABSTRACT FROM AUTHOR]

Identifying habitat that is essential to the recovery of species at risk, known as critical habitat, is a major focus of species at risk legislation, yet there has been little research on the degree to which these areas are protected. Here, we first review the provisions for protecting critical habitat on non‐federal lands within Canada's Species at Risk Act (SARA). Next, we use the declining southern mountain population of woodland caribou (Rangifer tarandus caribou) in British Columbia, Canada as a case study to show that identification of critical habitat does not guarantee its protection on non‐federal lands. Our analyses show that 909 km2 of critical habitat identified on provincial lands were logged in 5 years after it was legally identified under SARA. Existing provincial legislation and policies have provided incomplete protection of caribou critical habitat, and Canada's federal government has yet to exercise authority under SARA that could protect these areas. In the absence of nondiscretionary protection under provincial legislation, a combination of alternative mechanisms, involving all levels of government, Indigenous people, and industry, will be essential to protect critical habitat and help recover species at risk. [ABSTRACT FROM AUTHOR]

Introduction: The "tintal" is a type of seasonally inundated forest where the dominant species is Haematoxylum campechianum L. Due to its structural characteristics and the conditions of the areas where it develops, it could work as a critical habitat for many animal species. Objective: This work aimed at describing the regional and local diversity of the chiropterofauna inhabiting tintal along different areas in the Southeastern Mexico. Methods: The research was carried out in eight localities with presence of tintal in the states of Campeche and Tabasco, Mexico. In each site, six mist nets were placed during three nights. The observed and expected richness were calculated for each site, as well as the total abundance. Rank-abundance and species accumulation curves were generated. Similarity analyses between localities were performed and correlated with the geographical distance between them. Results: We recorded 25 bat species belonging to five families, where Phyllostomidae was the most represented. Most registered species were insectivorous (44 % of the total), while frugivorous were the most abundant. Frugivorous Artibeus lituratus and A. jamaicensis were the species recorded in a greater number of localities, and Glossophaga soricina was the most abundant. The highest richness of species was registered in Oxpemul (N= 12), while in Las Bodegas we found the lowest (N= 4), although the latter was the third locality with the highest number of individuals. The estimated richness of species for the whole area varied between 29 and 34. The least even assemblages were Las Bodegas and Tres Brazos. The most similar localities in terms of the structure of the assemblages were La Toza and Las Bodegas and, in terms of the species composition, Oxpemul and Atasta. The similarities between the localities were not correlated with geographical proximity. Conclusions: Most of the researched localities were highly anthropized, but the tolerance of several bat species to these landscape modifications has allowed them to make use of such areas. The high abundance of the frugivorous species registered supports that bats may play a key role in the recovery of tree vegetation in altered areas in Southeastern Mexico, and emphasizes the value of the tintal along this area for the conservation of biodiversity. [ABSTRACT FROM AUTHOR]

The Balearic Sperm Whale Project (BSWP) is a research collaboration between the University of St Andrews and Asociación TURSIOPS that has been studying the population of sperm whales that uses the deep waters to the south and east of Cabrera since 2003. Using acoustic tracking and photo-identification methods the research has shown that these waters are a critical habitat for this species, evidenced by both high densities and also the presence of both mature males and female social groups with calves. The Mediterranean sperm whale population is classified as "Endangered" by the IUCN because of its small size and vulnerability to anthropogenic threats. One of the gravest threats facing these large whales is being struck by ships, as documented by the BSWP with photographic records of individuals carrying visible injuries resulting from non-lethal collisions. It is however unknown how many animals fall victim to lethal collisions each year, and for those that are injured but survive, the effect of the injury on their fecundity and the subsequent cumulative impact on population growth are also unknown. Furthermore, the mere presence of high levels of maritime traffic can cause conservation issues if it causes animals to vacate critical habitat areas such as the waters around Cabrera. [ABSTRACT FROM AUTHOR]

Since the year 2000 and for more than a decade, several studies have explored different aspects of the complex life history of the bottlenose dolphin, Tursiops truncatus, in the waters around the Balearic Islands, using various techniques. However, despite the ecological importance of the species and its occurrence in the Cabrera Archipelago National Park, robust studies have not been developed to describe the relation of the species with the Park, and all existing information comes from projects carried out in the area with other objectives. The combination of available data now allows us to describe many of the characteristics of the bottlenose dolphin population that occurs in the Park. The deep waters of the Ibiza and Mallorca channel were found to act as a natural barrier limiting the movements of the species and structuring dolphins into two subpopulations, Gimnesias and Pitiüses, with some genetic differentiation. In addition to the high degree of geographical fidelity, there are isotopic differences among individuals sampled in nearby locations, indicating different feeding strategies that could be transmitted culturally. These specializations can also be observed in the interactions of the species with fishing activity. However, bottlenose dolphins are not the only cetaceans that can be observed around Cabrera. A total of 8 species of these marine mammals (that is, all species that are resident in the Mediterranean Sea) occur, to a greater or lesser extent, in the waters of the Park. [ABSTRACT FROM AUTHOR]

Irrawaddy dolphins (Orcaella brevirostris) are a globally Endangered cetacean species found in rivers, lakes, estuaries, and coastal waters across Southeast Asia. Whilst much attention has concentrated on understanding freshwater populations of the species, marine populations have received less research attention, with the majority of marine studies focusing on determining abundance and distribution. As part of The Cambodian Marine Mammal Conservation Project, the current study utilises a combination of year-long land and boat survey techniques to identify seasonal critical habitats for the species in Cambodia's Kep Archipelago, as well as fill knowledge gaps on the species' behavioural ecology, to contribute to the design of effective and tailored regional conservation strategies. Results showed Irrawaddy dolphins to be present in the Kep Archipelago in all seasons, with the highest encounter rates in Summer Monsoon (May-September) and Post-Monsoon (October-November) seasons, and the lowest encounter rates in Pre-Monsoon season (March-April). Juveniles were present in all seasons, suggesting the region represents an important nursing ground for the population. Foraging was the most commonly observed behaviour, with significant associations found between certain behavioural states and events, group sizes and seasons, group sizes and juvenile presence, and swim styles and juvenile presence. [ABSTRACT FROM AUTHOR]

Marine turtles are globally endangered species that spend more than 95% of their life cycle in in-water habitats. Nevertheless, most of the conservation, recovery and research efforts have targeted the on-land habitats, due to their easier access, where adult females lay their eggs. Targeting the large knowledge gaps on the in-water critical habitats of turtles, particularly in the Large Marine Ecosystem Gulf of Mexico, is crucial for their conservation and recovery in the long term. We used satellite telemetry to track 85 nesting females from their beaches after they nested to identify their feeding and residency habitats, their migratory corridors and to describe the context for those areas. We delimited major migratory corridors in the southern Gulf of Mexico and West Caribbean and described physical features of internesting and feeding home ranges located mainly around the Yucatan Peninsula and Veracruz, Mexico. We also contributed by describing general aggregation and movement patterns for the four marine turtle species in the Atlantic, expanding the knowledge of the studied species. Several tracked individuals emigrated from the Gulf of Mexico to as far as Nicaragua, Honduras, and the Bahamas. This information is critical for identifying gaps in marine protection and for deciphering the spatial connectivity in large ocean basins, and it provides an opportunity to assess potential impacts on marine turtle populations and their habitats.

In this study we describe how franciscana and Guiana dolphin habitat use is influenced by tidal cycles and seasonality in Babitonga Bay. The franciscanas use a greater area in winter and a smaller area in summer, but the extent of the area used did not vary with the tide. Guiana dolphins did not change the extent of the area used within seasons or tides. Franciscanas remained closer to the mouth of the bay and the islands during ebb tide, moving to the inner bay areas and closer to the mainland coast during flood tide. Guiana dolphin used areas closer to the mainland coast during the flood tide. Guiana dolphin patterns of movement do not seem to be related to the tidal current. Franciscanas used sandier areas while Guiana dolphins preferred muddy areas, with some seasonal variation. We suggest that these dolphins modify their distributions based on habitat accessibility and prey availability. This study enhances our knowledge of critical habitat characteristics for franciscana and Guiana dolphins, and these factors should be considered when planning local human activities targeting species conservation.

Abstract Selection and use of dens is a critical behavioral adaption of bears (Ursus spp.) to survive extended periods of resource limitation. We analyzed selection of den sites by brown bears (Ursus arctos) in an arctic montane environment from 2014 to 2017. We used GPS data from 51 instrumented bears to physically locate, identify, and describe den sites (n = 33) and to quantitatively model the selection of denning habitat (n = 65 dens over 3 yr). We conducted an analysis of den‐site selection at the home range (third order) scale using variables describing topographic, vegetative, and spatially‐explicit fish and wildlife models. We hypothesized four main factors influence den‐site selection by brown bears: (1) physiography, (2) proximity to food resources, (3) thermal insulation, and (4) den‐area fidelity. We used kernel density estimates to define space use and conditional logistic regression to estimate den selection within individual home ranges. Brown bears selected den sites on steep slopes (>31°) with high snow load potential near their previously used den site. Our results supported our hypothesis that den selection by brown bears was related to thermal insulation, structural stability, drainage, and den‐area fidelity.