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The current focus of river restoration on flow and sediment transfer without proper consideration of vegetation as a key structuring agent, beyond its stabilising effect, is too simplistic. We contend that vegetation has an essential role in shaping the physical fluvial environment and should be considered equally alongside hydrogeomorphic processes in restoration projects. In support, we introduce engineer plants as important controls, along with flowing water and transported sediments, on the morphodynamics of river systems and associated physical habitat development. The effect of vegetation on channel planform is then summarised, the influence of vegetation on hydrogeomorphic connectivity is outlined, and then the role of vegetation in landform development and habitat provision, as encapsulated in the fluvial biogeomorphic succession model, is described. We then present examples demonstrating how vegetation has contributed to the recovery of degraded rivers through biogeomorphic processes. Finally, we advance the concept of biogeomorphic river restoration by proposing principles to support a closer synthesis of the component sciences and list key areas for practitioners to focus on. Vegetation succession has a significance that goes beyond its physical structure or influence on sediment stability. In many river settings, it is central to channel evolution. The coupled assembly of plant communities and fluvial landforms affect the development of spatially and temporally dynamic habitat through biogeomorphic interactions. Restoration approaches that do not fully consider this dynamic may fail to anticipate river behaviour and recovery trajectories. [ABSTRACT FROM AUTHOR]

Apex predators have critical roles in maintaining the structure of ecosystem functioning by controlling intraguild subordinate populations. Such dominant–subordinate interactions involve agonistic interactions including direct or indirect impacts on the subordinates. As these indirect effects are often mediated through physiological processes, it is important to quantify such responses to better understand population parameters. We used a large carnivore intraguild system involving tiger (Panthera tigris) and leopard (Panthera pardus) to understand the dietary and physiological responses under a spatio-temporal gradient of tiger competition pressures in Rajaji Tiger Reserve (RTR) between 2015 and 2020. We conducted systematic faecal sampling in the winters of 2015 and 2020 from the park to assess diet and physiological measures. Analyses of leopard-confirmed faeces suggest a dietary-niche separation as a consequence of tiger competition. In 2020, we found an increased occurrence of large-bodied prey species without tiger competition in western-RTR. Physiological measures followed the dietary responses where leopards with large-sized prey in the diet showed higher fT3M and lower fGCM measures in western-RTR. In contrast, eastern-RTR leopards showed lower levels of fT3M and fGCM in 2020, possibly due to intense competition from tigers. Overall, these patterns strongly indicate a physiological cost of sympatry where competition with dominant tigers resulted in elevated nutritional stress. We recommend expansion of leopard monitoring and population estimation efforts to buffers, developing appropriate plans for human–leopard conflict mitigation and intensive efforts to understand leopard population dynamics patterns to ensure their persistence during the ongoing Anthropocene. [ABSTRACT FROM AUTHOR]

Abstract Background Habitat degradation is known to have a major impact on the composition of bird communities, yet how these communities recover following such disturbance is less understood. This study examined bird community changes from pre-logging to recovery over the course of habitat disturbance caused by the development of the Hulu Terengganu Hydroelectric Dam Project in Peninsular Malaysia, between 2007 and 2018. Bird surveys were conducted using point count observations and mist netting in the dam area from the pre-logging phase until the operation phase. Results It was observed that while bird species significantly declined after large-scale habitat clearance between the pre-logging and construction phases, they showed positive signs of recovery from the inundation to operation phases. These findings indicate that the bird community is still recovering, and the permanent loss of habitat required by most of the original species has not occurred, as evidenced by recolonisation. Bird species composition differed across phases due to varying habitat conditions. The turnover rate and immigration rate (recolonisation and newly recorded species) were higher between the construction and operation phases. It was also observed that insectivorous birds were more heavily affected than others by changes to the landscape, which highlights the versatility, survivability and tolerance of certain species to extreme disturbance and habitat modification. Conclusion Although the operation phase showed an incremental change in bird species richness due to recolonisation and newly recorded species, this value remains far from that of the pre-logging phase. We predict that bird species recovery will continue to increase for some time before reaching a plateau among the newly created islands, reservoir and catchment area of the dam.

Choosing effective methods to restore habitat for the diverse faunal assemblages of tropical forests is hampered by lack of long-term data comparing multiple restoration treatments. We conducted area counts of bird assemblages over 12 years (∼5–17 years since restoration) in a blocked experiment with two active planted treatments (tree plantations and applied nucleation) and a passive restoration treatment (natural regeneration) replicated at 11 sites in Costa Rica. We also surveyed six pastures and five remnant forest sites to assess recovery of avian species richness, composition, forest specialists, and range-restricted species in restoration plots relative to degraded and reference systems. Restoration treatments showed increased resemblance of avian assemblages to remnant forest over time. Applied nucleation proved equally effective as plantation, despite a reduced planted area, whereas natural regeneration recovered more slowly. Assemblage-level trends in avian species richness and compositional similarity to reference forest are underpinned by reductions in use by pasture birds and by gradual increases in richness of forest-affiliated species. Because forest-affiliated species tend to have narrower distributions than the open-country species they replace, forest restoration can reduce biotic homogenization at the local scale. Restoration practitioners should consider applied nucleation as an alternative to standard plantations if seeking rapid recovery of bird assemblages. However, the ecological return on investment from natural regeneration increases over a couple of decades. Managers should monitor trends in forest-affiliated and range-restricted species to track the recovery of the full avian assemblages, since coarse metrics like species richness and overall compositional similarity may plateau relatively quickly. [ABSTRACT FROM AUTHOR]

Background: Habitat degradation is known to have a major impact on the composition of bird communities, yet how these communities recover following such disturbance is less understood. This study examined bird community changes from pre-logging to recovery over the course of habitat disturbance caused by the development of the Hulu Terengganu Hydroelectric Dam Project in Peninsular Malaysia, between 2007 and 2018. Bird surveys were conducted using point count observations and mist netting in the dam area from the pre-logging phase until the operation phase. Results: It was observed that while bird species significantly declined after large-scale habitat clearance between the pre-logging and construction phases, they showed positive signs of recovery from the inundation to operation phases. These findings indicate that the bird community is still recovering, and the permanent loss of habitat required by most of the original species has not occurred, as evidenced by recolonisation. Bird species composition differed across phases due to varying habitat conditions. The turnover rate and immigration rate (recolonisation and newly recorded species) were higher between the construction and operation phases. It was also observed that insectivorous birds were more heavily affected than others by changes to the landscape, which highlights the versatility, survivability and tolerance of certain species to extreme disturbance and habitat modification. Conclusion: Although the operation phase showed an incremental change in bird species richness due to recolonisation and newly recorded species, this value remains far from that of the pre-logging phase. We predict that bird species recovery will continue to increase for some time before reaching a plateau among the newly created islands, reservoir and catchment area of the dam. [ABSTRACT FROM AUTHOR]

The catastrophic eruption of Mt. Pinatubo in 1991 destroyed the forests that covered the peak and impacted the surrounding habitat over a broad area of central Luzon. Information on the mammal fauna of Mt. Pinatubo prior to the eruption is limited but documents a variety of native mammals. In 2011 and 2012, we surveyed mammals at localities along an elevational gradient on the eastern slope of the mountain where vegetation had been devastated by pyroclastic flows and subsequent lahars, and habitat reflected early stages of plant succession. We documented eight species of bats (five fruit bats and three insectivorous bats), seven species of small nonvolant mammals (two non-native and five native rodents), and two native large mammals. Additional species of bats and non-volant mammals present in the vicinity of Mt. Pinatubo prior to the eruption or recently documented at other localities in the Zambales Mountains may be present in remnant forest habitat elsewhere on Pinatubo. Across five survey localities where habitat was in the early stages of regeneration, native species of small non-volant mammals were more widespread and much more abundant than were non-natives. The most abundant native species, Apomys sacobianus, may be endemic to Mt. Pinatubo. It is an extreme example of a "disturbance specialist" that thrives in a severely disturbed habitat. Results underscore the disturbance tolerance of many native small mammals of Luzon and reveal a resilience that is remarkable for a highly endemic insular fauna. Mt. Pinatubo presents opportunities for further studies on how natural disturbance has shaped the evolution of the Philippine biota and may influence its future conservation. [ABSTRACT FROM AUTHOR]

The San Clemente Bell′s Sparrow (Artemisiospiza belli clementeae) is a federally threatened subspecies endemic to San Clemente Island, California. Previous research suggested dependence on boxthorn (Lycium californicum) as breeding habitat and nesting substrate; however, this conclusion was based on data collected when introduced feral ungulates had severely degraded the soil and vegetation cover. Since removal of the ungulates, native vegetation has gradually increased and the San Clemente Bell′s Sparrows have expanded into areas where habitat had been unsuitable. To explore how Bell′s Sparrows use these areas, we examined reproductive metrics associated with habitat covariates gathered at 214 nest sites used by Bell′s Sparrows from 2014 to 2016. We found that nest success in boxthorn habitat, previously considered an essential habitat for Bell′s Sparrow nesting, was similar to success in alternative habitat types. Our findings contradict previous conclusions that Bell′s Sparrows were boxthorn-dependent. We believe this previously documented relationship was likely due to the lack of available alternative nesting habitat following years of feral ungulate degradation, and Bell′s Sparrows now reproduce in multiple habitat types and throughout most of San Clemente Island. Furthermore, our findings illustrate the importance of long-term monitoring and corresponding adaptive management when monitoring species in changing and recovering landscapes. [ABSTRACT FROM AUTHOR]

Five species of aquatic crambid moths of the genus Petrophila were discovered in Oak Creek, Arizona. The biology and immatures stages of P. avernalis, P. longipennis, P. anna, and P. cornvillia are described for the first time. The biology of the fifth species, P. jaliscalis, had been previously described. Long-term studies identified environmental factors that influence their distribution and abundance. Species richness is related to complexity of the aquatic habitat while abundance is related to environmental parameters and behavior. The negative impact of one natural and one human-made disruption to the aquatic environments were monitored and Petrophila larvae were found to be excellent indicators of both the disruption and subsequent recovery of the habitat. [ABSTRACT FROM AUTHOR]

Dam removal is becoming an effective approach for aquatic biodiversity restoration in damming river in order to balance the aquatic ecosystem conservation with large-scale cascade damming. However, the effects of dam removal on fish communities in Asian mountainous rivers, which are dominated by Cypriniformes fishes, are still not well known. To determine whether dam removal on a mountainous river benefit restoration of fish diversity, we investigated the response of fish assemblage to dam removal using a before- after-control-impact design in two tributaries of the Lancang River (dam removal river: the Jidu River, and control river: the Fengdian River). Fish surveys were conducted one year prior to dam removal (2012) and three years (2013-2015) following dam removal. We observed rapidly and notably spatio-temporal changes in fish biodiversity metrics and assemblage structure, occurring in the Jidu River within the first year after dam removal. Overall, fish species richness, density and Shannon-Wiener diversity all increased immediately in above- and below-dam sites, and maintained a stable level in subsequent years, compared to unchanged situation in the control river. All sites in the Jidu River experienced shifts in fish composition after dam removal, with the greatest temporal changes occurred in sites below- and above- the former dam, resulting in a temporal homogenization tendency in the dam removed river. These findings suggest that dam removal can benefit the recovery of habitat conditions and fish community in Asian mountainous rivers, but the results should be further evaluated when apply to other dammed rivers since the dam age, fluvial geomorphology and situation of source populations could all affect the responses of fish assemblages. [ABSTRACT FROM AUTHOR]

The territorial waters of Qatar once supported dense assemblages of the pearl oyster Pinctada radiata. The oysters settled on a patchy network of limestone platforms (hairãt) and provided a suite of ecosystem services to the surrounding marine environment. Commercially important fish species are associated with hairãt and as a result, industrial fishing with traps focused on these areas. This study has shown that heavily-fished areas are presently in a state which can be considered non-favorable to conservation while areas closed to fishing are recovering. It is probable that an increase in fishing activity using traditional Gargoor traps and grapple retrieval are responsible for the current ecological status of the hairãt. The intensity in trap fishing appears to be having a detrimental effect on species such as corals, sea grasses and oysters. The decline in the standing stock of oysters is dramatic with an estimated reduction ratio of 580:1 between 2002 and 2016. As fishing damage appears to be a significant contributor to these losses, measures such as spatial protection of productive shallow offshore habitats and restriction on fishing effort are urgently required to address the decline. Strategic oyster stock enhancement through the re-seeding of selected areas could boost the recovery of damaged hairãt as P. radiata ecosystem services return. [ABSTRACT FROM AUTHOR]

Natural regeneration of seismic lines, cleared for hydrocarbon exploration, is slow and often hindered by vegetation damage, soil compaction, and motorized human activity. There is an extensive network of seismic lines in western Canada which is known to impact forest ecosystems, and seismic lines have been linked to declines in woodland caribou (Rangifer tarandus caribou). Seismic line restoration is costly, but necessary for caribou conservation to reduce cumulative disturbance. Understanding where motorized activity may be impeding regeneration of seismic lines will aid in prioritizing restoration. Our study area in west-central Alberta, encompassed five caribou ranges where restoration is required under federal species at risk recovery strategies, hence prioritizing seismic lines for restoration is of immediate conservation value. To understand patterns of motorized activity on seismic lines, we evaluated five a priori hypotheses using a predictive modeling framework and Geographic Information System variables across three landscapes in the foothills and northern boreal regions of Alberta. In the northern boreal landscape, motorized activity was most common in dry areas with a large industrial footprint. In highly disturbed areas of the foothills, motorized activity on seismic lines increased with low vegetation heights, relatively dry soils, and further from forest cutblocks, while in less disturbed areas of the foothills, motorized activity on seismic lines decreased proportional to seismic line density, slope steepness, and white-tailed deer abundance, and increased proportional with distance to roads. We generated predictive maps of high motorized activity, identifying 21,777 km of seismic lines where active restoration could expedite forest regeneration. [ABSTRACT FROM AUTHOR]

We here report the first sign of amphibian recovery after a strong decline due to acidic precipitation over many decades and peaking around 1980-90. In 2010, the pH level of ponds and small lakes in two heavily acidified areas in southwestern Scandinavia (Aust-Agder and Østfold in Norway) had risen significantly at an (arithmetic) average of 0.14 since 1988-89. Parallel with the general rise in pH, amphibians (Rana temporaria, R. arvalis, Bufo bufo, Lissotriton vulgaris, and Triturus cristatus) had become significantly more common: the frequency of amphibian localities rose from 33% to 49% (n = 115), and the average number of amphibian species per locality had risen from 0.51 to 0.88. In two other (reference) areas, one with better buffering capacity (Telemark, n = 21) and the other with much less input of acidic precipitation (Nord-Trøndelag, n = 106), there were no significant changes in pH or amphibians. [ABSTRACT FROM AUTHOR]

Asiatic fungus Cryphonectria parasitica has gradually infected all chestnut habitats, forest and horticulture plantations from the most important natural centres of sweet chestnut distribution in Romania. The objectives of this work were to understand the destruction rate of chestnut habitats under C. parasitica pressure, and to test the efficacy of pathogen control in revitalizing these protected forests. Successive inventories of forest health status were carried out in forest districts of Maramures and Gorj counties. C. parasitica biologic control using CHV1 virus has been tested. The methodology includes standard laboratory and field work techniques: local hipervirulent strain identification and conversion to hipovirulence, field canker inoculation, and treatment efficacy evaluation. The fungus killed all mature chestnut trees in roughly two decades. Field inoculation has been successful on chestnut and sessile oak (fungus secondary host) in experimental plots from both target zones. This is the first time in Romania when a forest habitat is recovered by means of biological control, after a severe dieback of the old forest caused by a lethal invasive pathogen. [ABSTRACT FROM AUTHOR]

Sea lamprey ( Petromyzon marinus ) and allis shad ( Alosa alosa ) have been fished for centuries in mainland Portugal during their upstream spawning migration. Here, biological information is compared for the two species and governance and monitoring data from Portugal are reviewed to propose species-specific courses of future action. Despite a national fisheries legislation common for the two species and the designation of Sites of Community Interest (SCIs) for both, the current conservation needs for sea lamprey and allis shad in Portugal are considered to be distinct. For sea lamprey, conservation priorities must focus on planning fisheries management in articulation with habitat recovery to guarantee cost-effective monitoring and sustainable long-term exploitation that adds value to local communities and pays due taxation. On the contrary, conservation concerns and actions for allis shad must strengthen and be more proactive in the reduction of fishing mortality, both target (in rivers) and bycatch (at sea). There is a need to make better use of the opportunities inherent in the Habitats Directive and the possibility to define specific management actions within SCIs. To this effect, it will be necessary to revise existing legislation and guarantee better articulation between jurisdictional authorities. A good example in this direction is the articulation already established in the river Mondego where habitat restoration, fish monitoring and effective species-specific fisheries control measures have been taken and implemented in recent years by a large institutional partnership. [ABSTRACT FROM AUTHOR]

Conflicts between local people's livelihoods and conservation have led to many unsuccessful conservation efforts and have stimulated debates on policies that might simultaneously promote sustainable management of protected areas and improve the living conditions of local people. Many government-sponsored payments-for-ecosystem-services (PES) schemes have been implemented around the world. However, few empirical assessments of their effectiveness have been conducted, and even fewer assessments have directly measured their effects on ecosystem services. We conducted an empirical and spatially explicit assessment of the conservation effectiveness of one of the world's largest PES programs through the use of a long-term empirical data set, a satellite-based habitat model, and spatial autoregressive analyses on direct measures of change in an ecosystem service (i.e., the provision of wildlife species habitat). Giant panda (Ailuropoda melanoleuca) habitat improved in Wolong Nature Reserve of China after the implementation of the Natural Forest Conservation Program. The improvement was more pronounced in areas monitored by local residents than those monitored by the local government, but only when a higher payment was provided. Our results suggest that the effectiveness of a PES program depends on who receives the payment and on whether the payment provides sufficient incentives. As engagement of local residents has not been incorporated in many conservation strategies elsewhere in China or around the world, our results also suggest that using an incentive-based strategy as a complement to command-and-control, community- and norm-based strategies may help achieve greater conservation effectiveness and provide a potential solution for the park versus people conflict. [ABSTRACT FROM AUTHOR]

Many dragonfly species in The Netherlands declined in the 20th century because of acidification, eutrophication, and desiccation of lotic and lentic habitats and canalization of streams and rivers. These pressures peaked in the 1970s, when 26 of 65 native species had an unfavorable conservation status on the 1997 Dutch Red List. Since the 1980s, environmental regulations have led to improved water quality, and many habitat restoration projects have been carried out. We used standardized monitoring data (1999–2013) and unstandardized observations (1991–2013) to investigate how dragonflies have changed in the last 20 y on a national scale. We compared trends of dragonfly species from different habitat types and with southern vs northern distribution in Europe. Dragonflies recovered strongly in The Netherlands in a period of ∼20 y, probably because of recent habitat improvements. Lotic species have benefitted more than lentic species, and southern species have more positive trends than northern species, suggesting that climate change has contributed to the recovery. Dragonflies were resilient and able to quickly recover when their habitats were restored. Recovery has led to a better conservation status for many species. Unstandardized data delivered results consistent with those from monitoring data and had greater statistical power to detect trends because many more unstandardized data than standardized data were available. Thus, when the goal is to provide a general overview of changes in dragonflies, unstandardized data can outperform standardized abundance data. However, abundance data may deliver complementary information for individual species. Our results support the suitability of dragonflies as indicators of freshwater habitat condition, but they recover more strongly in The Netherlands than many other insects, possibly because of their higher dispersal abilities or different habitat requirements. [ABSTRACT FROM AUTHOR]

A previous study on the effects of experimental hydraulic clam dredging on seabed habitat and commercial bivalve populations revealed a lack of recovery after a 3-year post-dredging period (1998–2001) on a deep (65–75 m) offshore sandy bank on the Scotian Shelf, Canada. Follow-up sidescan sonar surveys were carried out 5 and 10 years after dredging (2003, 2008) in order to identify long-term processes of seabed recovery. Grab sampling was carried out 10 years after dredging to identify post-dredging commercial bivalve recruitment. Changes in the seafloor, including dredge tracks, were documented with a series of 7 sidescan sonar surveys between 1998 and 2008. A sediment mobility model was constructed based on modeled tidal current and hindcast wave data over this time period to quantify natural seabed disturbance and interpret changes to the dredge tracks mapped by sidescan sonar surveys. The model indicated that tidal currents had minimal effect on sediment mobilization. The main driving force associated with re-working of surficial sediments as evidenced by deterioration of dredge tracks in sonograms was annual fall/winter storms. While the annual frequency of storms and associated wave heights was variable, the observations and sediment mobility calculations suggest that the most influential variable is the magnitude of individual large storms, specifically storms with a significant wave height of ∼11 m. These storms are capable of generating mobile sediment layers of 20–30 cm thickness, equivalent to the dredge blade cutting depth. It appears that, with minor exceptions, sediment properties have returned to pre-dredging conditions 10 years after dredging in this habitat. Based on known age-length relationships, the four commercial bivalve species showed very low recruitment at the experimental site over the 10-year post-dredging period. However, this is unlikely due to a dredging effect since a similar pattern was observed in non-dredged areas. [ABSTRACT FROM AUTHOR]

Riparian and quaking aspen (Populus tremuloides) woodlands are centers of avian abundance and diversity in the western United States, but they have been affected adversely by land use practices, particularly livestock grazing. In 1990, cattle were removed from a 112,500-ha national wildlife refuge in southeastern Oregon. Thereafter, we monitored changes in vegetation and bird abundance in years 1-3 (phase 1) and 10-12 (phase 2) in 17 riparian and 9 snow-pocket aspen plots. On each 1.5-ha plot, we sampled vegetation in 6 transects. Three times during each breeding season, observers recorded all birds 50 m to each side of the plot's 150-m centerline for 25 minutes. We analyzed data with multivariate analysis of variance and paired t tests with p values adjusted for multiple comparisons. In both periods, riparian and snow-pocket aspen produced extensive regeneration of new shoots ( stems/ha and 7079 stems/ha, respectively). By phase 2, a 64% increase in medium-diameter trees in riparian stands indicated successful recruitment into the overstory, but this pattern was not seen in snow-pocket stands, where the density of trees was over 2 times greater. By phase 2 in riparian and snow-pocket stands, native forb cover had increased by 68% and 57%, respectively, mesic shrub cover had increased by 29% and 58%, and sagebrush cover had decreased by 24% and 31%. Total avian abundance increased by 33% and 39% in riparian and snow-pocket aspen, respectively, ground or understory nesters increased by 133% and 67% and overstory nesters increased by 34% and 33%. Similarly, ground or understory foragers increased by 25% and 32%, aerial foragers by 55% and 57%, and overstory foragers by 66% and 43%. We interpreted the substantial regeneration of aspen shoots, increased densities of riparian forbs and shrubs, and increased avian abundances as a multitrophic-level response to the total removal of livestock and as substantial movement toward recovery of biological integrity. [ABSTRACT FROM AUTHOR]

Abstract: Over 1990–1998, the Mondego estuary, Portugal, experienced profound modifications due to eutrophication, culminating in the disappearance and replacement of Zostera noltii by opportunistic macroalgae in the inner most disturbed areas. A decade after restoration measures implementation, Z. noltii started to gradually recolonize the inner parts, following 20 years of absence. This work explores the factors underlying successful Z. noltii recolonization and its subsequent implications on a mud snail Hydrobia ulvae population. During the macroalgal bloom, highest values in H. ulvae abundance, biomass and production were recorded, strongly declining afterwards. Three recovery attempts characterized the post-restoration phase, with considerably increases in H. ulvae abundance, biomass and production since Z. noltii reappearance. The seagrass provided long-term protection and abundant food resources for reproductive adults, contrarily to the ephemeral macroalgae. Through time, large size individuals increased, becoming the population more stable, structured and similar to the one inhabiting the “original”Z. noltii meadows. [Copyright &y& Elsevier]

Aim Local-scale diversity patterns are not necessarily regulated by contemporary processes, but may be the result of historical events such as habitat changes and selective extinctions that occurred in the past. We test this hypothesis by examining species-richness patterns of the land snail fauna on an oceanic island where forest was once destroyed but subsequently recovered. Location Hahajima Island of the Ogasawara Islands in the western Pacific. Methods Species richness of land snails was examined in 217 0.25 × 0.25 km squares during 1990–91 and 2005–07. Associations of species richness with elevation, current habitat quality (proportion of habitat composed of indigenous trees and uncultivated areas), number of alien snail species, and proportion of forest loss before 1945 in each area were examined using a randomization test and simultaneous autoregressive (SAR) models. Extinctions in each area and on the entire island were detected by comparing 2005–07 records with 1990–91 records and previously published records from surveys in 1987–91 and 1901–07. The association of species extinction with snail ecotype and the above environmental factors was examined using a spatial generalized linear mixed model (GLMM). Results The level of habitat loss before 1945 explained the greatest proportion of variation in the geographical patterns of species richness. Current species richness was positively correlated with elevation in the arboreal species, whereas it was negatively correlated with elevation in the ground-dwelling species. However, no or a positive correlation was found between elevation and richness of the ground-dwelling species in 1987–91. The change of the association with elevation in the ground-dwelling species was caused by greater recent extinction at higher elevation, possibly as a result of predation by malacophagous flatworms. In contrast, very minor extinction levels have occurred in arboreal species since 1987–91, and their original patterns have remained unaltered, mainly because flatworms do not climb trees. Main conclusions The species-richness patterns of the land snails on Hahajima Island are mosaics shaped by extinction resulting from habitat loss more than 60 years ago, recent selective extinction, and original faunal patterns. The effects of habitat destruction have remained long after habitat recovery. Different factors have operated during different periods and at different time-scales. These findings suggest that historical processes should be taken into account when considering local-scale diversity patterns. [ABSTRACT FROM AUTHOR]

Rapid growth in marine sand mining for construction and other uses poses environmental challenges to coastal nations virtually worldwide. Yet the development of management policies, such as a system of fees imposed on operators for damage caused by mining, has been frustrated by a lack of studies to support such measures. Adapting a Beverton-Holt bioeconomic model, this paper attempts to contribute to the estimation of external costs to commercial fisheries due to marine mining. Using the major mining area of Ongjin in Korea as a case study, we estimate economic losses in use value of commercial fisheries through the time to recovery of the injured resource stocks. Present value of lost catch over a 1-year period from mining to resource recovery is estimated at $38,851 for a single “prototype” mining site. Estimated cumulative damages due to recurring mining for 5 and 10 years are $1.5 million and $2.2 million, respectively, at 20 mining sites. Sensitivity analyses are used to examine the effects of alternative assumptions to assess the many sources of uncertainty. Using a form of meta-analysis, dose-response information is used to assess the excess mortality the mining sediment plume has on eggs and larvae and, ultimately, on the value of lost catch ($841). Also addressed is the importance of specifying the appropriate “premining” conditions against which to assess environmental losses at the mining site. Damages estimated with premining fish populations are $23,066 higher than is the case using postmining conditions. Overall, the illustrative results suggest the variety of complex conditions which influence damage to fisheries from mining and which can benefit from further study to improve management guidelines. [ABSTRACT FROM AUTHOR]

There are approximately 650 known vessel groundings that occur annually within the Florida Keys National Marine Sanctuary (FKNMS). The majority of these groundings directly impact valuable seagrass habitat. The National Oceanic and Atmospheric Administration (NOAA), under the National Marine Sanctuary Act, and the State of Florida, under Florida statutes, act as co-trustees with the authority to recover monetary damages and restore injuries to the natural resources of the FKNMS. Previously, it was difficult to accomplish assessment and restoration planning for many of these incidencts in a cost-effective manner. With the goal of expediting development of litigation-quality natural resource damage claims for seagrass grounding incidents, NOAA has developed and implemented standardized damage assessment, restoration planning, and restoration scaling protocols for seagrass injuries. The protocols center around three major components: 1) GIS-based field assessment, 2) model-based estimation of injury recovery rates, and 3) calculation of compensation using Habitat Equivalency Analysis. By standardizing the assessment and restoration planning procedures associated with these types of incidents, NOAA and the States of Florida have substantially lowerd the threshold for the size and severity of grounding injuries that can be cost-effectively assessed and restored, significantly increasing the number of cases that can be addressed annually. In addition to the direct resource benefits of increased assessment and restoration, we anticipate that there will also be a deterrent effect on future groundings. [ABSTRACT FROM AUTHOR]

A hydraulic clam dredging experiment was conducted on a deep (70–80 m) offshore sandy bank on the Scotian Shelf in order to examine the immediate impacts of hydraulic dredging on physical habitat and to follow processes of recovery over a 3-year period. Seabed structural complexity in this low-relief habitat consists of small-scale sedimentary features including pits and bivalve burrow openings as well as polychaete tubes and empty mollusc shells. The most obvious effect of dredging was a dramatic change in seabed topography due to the numerous deep (20 cm), wide (4 m) curvilinear furrows that were cut by the dredges. The loss of burrows, tubes, and shells through destruction or burial, and local sedimentation created a smooth surface. Both spatial scale and sampling resolution were critical in identifying longer-term impacts. Dredge furrows were no longer visible in video 1 year after dredging due to their low relief; however, they persisted, while undergoing changes, as evidenced in sidescan sonograms. The margins of furrows were gradually degraded, likely through the combined actions of slumping, sediment transport and bioturbation. Over time, dredge furrows act as traps for empty shells. Differences in patterns of acoustic reflectance between dredge furrows and the surrounding seabed indicate long-lasting effects on sediment structure. Densities of large burrows were reduced by up to 90% after dredging with no signs of recovery after 3 years due to the high mortalities of their architect, the propellerclam, Cyrtodaria siliqua. Dredging effects were detectable against a background of natural temporal (annual) and large-scale spatial variability in physical habitat. [Copyright &y& Elsevier]

In 1970, approximately 2000 m3 of Bunker C crude oil impacted 300 km of Nova Scotia’s coastline following the grounding of the tanker Arrow. Only 10% of the contaminated coast was subjected to cleanup, the remainder was left to cleanse naturally. To determine the long-term environmental impact of residual oil from this spill event, samples of sediment and interstitial water were recovered in 1993, 1997 and 2000 from a sheltered lagoon in Black Duck Cove. This heavily oiled site was intentionally left to recover on its own. Visual observations and chemical analysis confirmed that substantial quantities of the weathered cargo oil were still present within the sediments at this site. However, direct observations of benthic invertebrate abundance suggest that natural processes have reduced the impacts of the residual oil. To confirm this hypothesis, sediment and interstitial water samples from Black Duck Cove were assessed with a comprehensive set of biotests and chemical assays.Residual oil in the sediments had limited effect on hepatic CYP1A protein levels and mixed function oxygenase (MFO) induction in winter flounder (Pleuronectes americanus). No toxicity was detected with the Microtox solid phase test (Vibrio fischeri). Significant sediment toxicity was detected by the amphipod survival test (Eohaustorius estuarius) in four out of the eight contaminated sediments. Interstitial water samples were deemed non-toxic by the Microtox 100% test (Vibrio fischeri) and the echinoid fertilization test (Lytechinus pictus). Sediment elutriates were also found to be non-toxic in the grass shrimp embryo-larval toxicity (GSELTOX) test (Palaemonetes pugio).Recovery at this contaminated site is attributed to natural processes that mediated biodegradation and physical removal of oil from the sediments. In support of the latter mechanism, mineralization experiments showed that all test sediments had the capacity for hexadecane, octacosane and naphthalene degradation, while chemical analysis confirmed that the Bunker C oil from the Arrow had undergone substantial biodegradation. [Copyright &y& Elsevier]

Following the restoration of natural conditions by reducing human pressures, reforestation is currently considered a possible option to accelerate the recovery of seagrass habitats. Long-term monitoring programs theoretically represent an ideal solution to assess whether a reforestation plan has produced the desired results. Here, we report on the performance of a 20 m2 patch of Posidonia oceanica transplanted on dead matte twelve years after transplantation in the Gulf of Palermo, northwestern Sicily. Photo mosaic performed in the area allowed us to detect 23 transplanted patches of both regular and irregular shape, ranging from 0.1 to 2.7 m2 and an overall surface close to 19 m2. Meadow density was 331.6 ± 17.7 shoot m−2 (currently five times higher than the initial value of 66 shoots m−2), and it did not show statistical differences from a close by natural meadow (331.2 ± 14.9). Total primary production, estimated by lepidochronology, varied from 333.0 to 332.7 g dw m2/year, at the transplanted and natural stand, respectively. These results suggest that complete restoration of P. oceanica on dead matte is possible in a relatively short time (a decade), thus representing a good starting point for upscaling the recovery of the degraded meadows in the area. [ABSTRACT FROM AUTHOR]

Degraded ecosystems worldwide are in need of restoration in order to recover essential ecosystem services, promoting biodiversity and enhancing carbon stock. Methods to restore vegetation differ widely in economic cost and effectiveness, but economic evaluations are scarce in the literature. The aim was to perform an economic appraisal of different restoration options for gypsum habitats after mining, analysing the effectiveness of the most feasible options comparing both, ecological success (survival) and economic (costs). The evaluated restoration techniques differed significantly in costs. The most expensive option was planting (69,795.50 €/ha), despite the high survival achieved. The least expensive successful option was manual sowing in level plots (0−15 % incline; 12,513.20 €/ha). The application of organic amendments proved expensive without offering substantial benefits, while the erosion-control blankets (ECBs) justified the cost only on steep slopes (50–60 % incline). We conclude that for relatively level areas without stability or erosion problems, the simplest and least expensive solution is manual sowing of native species. For steep areas (15−60 %), hydroseeding with dense mulching is the most cost-effective choice, while only small patches with steeper slopes (around 60 %) should be treated with ECBs to prevent excessive erosion and landslides. Restoration requires more ecological research followed by proper economic assessment in order to offer valuable solutions for practitioners, not only in mining restoration, but also in all types of ecological restoration. [ABSTRACT FROM AUTHOR]

The 2011 spill at platforms B and C of the Penglai 19-3 oil field in the Bohai Sea has been the worst oil spill accident in China. To assess long-term effects, a comprehensive monitoring program of chemical and biological variables (within a 2.2 km radius of the spill site) was conducted five years after the spill. Comparison of nutrient, Chl- a and oil concentrations in seawater, TOC, PAHs, heavy metals concentrations within the sediments, and the abundance and biomass of macrobenthic organisms to values obtained before and after the oil spill in previous studies indicate habitat recovery has occurred within the Bohai Sea following the episodic oil release. Observed elevated oil concentration in the water column and higher concentrations of two heavy metals, five PAHs, TOC, TOC/TN and lower values of δ13C, together with a reduction in macrobenthic biomass in near-field samples, suggest the influence of contaminants from chronic releases of oil and operational waste discharges within the vicinity of the oil platforms. Image 1 • Ecological impacts of an oil spill in the Bohai Sea were studied. • Significant levels of habitat recovery occurred within 5 years. • Environment near the platform remain a concern as a result of chronic inputs. Significant levels of habitat recovery occurred in the Bohai Sea five years after the oil spill, however, the environment near the platform remains a concern as a result of chronic inputs. [ABSTRACT FROM AUTHOR]

We investigated the effects of a catastrophic typhoon on mollusc assemblages of damaged mangrove plantations of different ages. Molluscs were sampled from infaunal, epifaunal and arboreal assemblages of mangrove stands in Lingayen Gulf, northwest Philippines, and compared with assemblages of un-impacted areas. Prior to the occurrence of the typhoon, there were clear shifts in the species diversity (H') and composition of mollusc assemblages with stand age of mangrove forests. This was observed in species composition through the succession in dominance from pioneer to seral or putative climax species, and assemblage type (as arboreal, epifaunal and infaunal). However, severe damage to vegetation structure and sediment properties (associated with a reduction in tree density and canopy cover resulting in increased temperatures and exposure) following the typhoon resulted in an alteration of trajectory patterns in the damaged stands. There were shifts in species composition and dominant species from having mature mangrove-associated species (pre-typhoon) to an abrupt return in dominance of pioneer species (post-typhoon). The damage was more evident in older stands than in intermediate-aged stands. Furthermore, the reduced presence of molluscs (and also probably their activities, i.e. burrowing) may have contributed to the delayed recovery of mangroves. The prospects for recovery of the system to pre-typhoon levels are therefore uncertain where the re-establishment of seral or edaphic mollusc assemblages appears to be related to the recovery of vegetation and sediment conditions. • Severe damage to vegetation structure and sediment properties (associated with a reduction in tree density and canopy cover resulting in increased temperatures and exposure) following the typhoon resulted in an alteration of trajectory patterns in the damaged stands. • There were shifts in species composition and dominant species from having mature mangrove-associated species (pre-typhoon) to an abrupt return in dominance of pioneer species (post-typhoon). • The reduced presence and activities of molluscs (i.e. as bioturbation) may have contributed to the delayed recovery of mangroves. [ABSTRACT FROM AUTHOR]