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The coastal waters of southern British Columbia, Canada, encompass habitat of international conservation significance to coastal and marine birds, including sizeable areas designated in the early 1900s as Migratory Bird Sanctuaries (MBS) to protect overwintering waterfowl from hunting near urban centres. Two of these, Shoal Harbour (SHMBS) and Victoria Harbour (VHMBS), have seen significant marine infrastructure development in recent decades and experience considerable vessel traffic. Vessel-related stressors are known to affect waterbirds, but traffic characteristics in coastal urban areas are poorly understood for the smaller vessels not tracked by Automatic Identification Systems (AIS). We conducted a pilot study using shore-based observers to develop small-vessel baselines for the winter months, when regional waterbird numbers are highest. During our surveys we recorded considerable inter-site variability in vessel traffic characteristics, with one site (SHMBS) a source of nearly twice as many vessel transits as the other (VHMBS). Most recorded vessels were small watercraft (mean length 26 ± 17′, mode 18′), and vessels at the high-traffic site were both shorter and faster on average. One in six vessels were classified as 'noisy', of interest given that noise is an important component of vessel disturbance of waterbirds and other marine animals. Few vessels (7% of all recorded) were of the type required to carry AIS transponders, which highlights the monitoring gap created by using AIS-based approaches alone in nearshore waters, and allows for correction of AIS-derived vessel counts. Waterbird community composition also varied by locality, with one site dominated by gulls (Laridae), cormorants (Phalacrocoracidae), and seaducks (Tribe Mergini), and the other by gulls, cormorants, and alcids (Alcidae). Our results demonstrate that fine-scale local variability must be taken into account when managing for vessel traffic disturbance of waterbirds, particularly at sites of high human population density and increasing coastal development. [ABSTRACT FROM AUTHOR]

How birds use and interact with an urban environment has been of interest for a variety of species across the globe. This has particularly been the case for gulls (Laridae) as species in this family nest and otherwise occupy habitat in urban areas on six continents, often coming into conflict with humans as they do so. In this study, we combine survey data of urban-nesting Glaucous-winged Gulls Larus glaucescens in Vancouver, Canada with detailed information on architectural and spatial features of the structures on which they nest to build an explanatory and predictive statistical model for nest-site selection in our study city. We find that building height is by far the most important explanatory variable in this selection process and that rooftops of higher structures are generally more attractive to nesters, but only up to a certain point. Flat rooftops in non-residential areas that are near water are also highly valued. However, complex relationships exist between these and other variables that offer detailed insights into urban nesting patterns. We use our modelling approach to predict that roughly 1,800 pairs of Glaucous-winged Gulls nested in the city in 2017 and over 2,000 pairs nested in the city in 2023. Combining this with high exact nest and rooftop recurrence rates derived from additional survey data taken between 2015 and 2019, and with historical population data, we argue that this urban population is likely to continue to expand in the near future at roughly 4% per annum. As this species has suffered declines in its natural breeding colonies across the region, this suggests its future in the region may be increasingly urban-centric. • Field observations combined with building features to predict urban nesting via GAMs. • Roughly 2000 pairs of Glaucous-winged Gulls nest across the City of Vancouver, Canada. • This urban population is growing at a rate of roughly 4% per annum. • Nest site fidelity is approximately 80%–90% per annum. • Building height is the most important built feature that predicts nest occurrence. [ABSTRACT FROM AUTHOR]

Unpublished accounts indicate that the number of Tufted Puffin Fratercula cirrhata colonies in western Canada has declined in recent decades. However, a lack of recent colony count data makes it impossible to determine current trends. Here we compile published and unpublished information for Tufted Puffins in the Canadian portion of the California Current System (i.e., from the vicinity of the Scott Islands south to the Canada-US border) to update understanding of the species' status in the region, and to assemble available information in a single source. We found historical records of three additional colonies over those in pre-existing compilations, bringing the total count for the region to 19. However, 11 of these are currently extirpated and another three likely so. All but one of these extirpated colonies are 'very small' (historical mode of counts, 1-3 pairs), reflecting patterns of Tufted Puffin colony loss in US waters to the south. Two larger puffin colonies (historical counts, 20-50 pairs) underwent abandonment in the 1990s, but one of these appears to have been recolonized recently. Tufted Puffin numbers at Canada's largest colony, Triangle Island, are likely stable. A lack of standardized monitoring of these colonies, with the exception of Triangle Island, makes it challenging to understand population trends, undertake restoration work, or mitigate current threats. [ABSTRACT FROM AUTHOR]

Measurements of naturally occurring stable isotopes in tissues of seabirds and their prey are a powerful tool for investigating long-term changes in marine foodwebs. Recent isotopic (δ15N, δ13C) evidence from feathers of Glaucous-winged Gulls (Larus glaucescens) has shown that over the last 150 years, this species shifted from a midtrophic marine diet to one including lower trophic marine prey and/or more terrestrial or freshwater foods. However, long-term isotopic patterns of δ15N and δ13C cannot distinguish between the relative importance of lower trophic-level marine foods and terrestrial sources. We examined 48 feather stable-hydrogen (δ²H) and -sulfur (δ34S) isotope values from this same 150-year feather set and found additional isotopic evidence supporting the hypothesis that gulls shifted to terrestrial and/or freshwater prey. Mean feather δ²H and δ34S values (±SD) declined from the earliest period (1860-1915; n = 12) from −2.5 ± 21.4‰ and 18.9 ± 2.7 ‰, respectively, to −35.5 ± 15.5 ‰ and 14.8 ± 2.4 ‰, respectively, for the period 1980-2009 (n = 12). We estimated a shift of ~30% increase in dependence on terrestrial/freshwater sources. These results are consistent with the hypothesis that gulls increased terrestrial food inputs in response to declining forage fish availability. [ABSTRACT FROM AUTHOR]

The world's oceans have undergone significant ecological changes following European colonial expansion and associated industrialization. Seabirds are useful indicators of marine food web structure and can be used to track multidecadal environmental change, potentially reflecting long-term human impacts. We used stable isotope ( δ13C, δ15N) analysis of feathers from glaucous-winged gulls ( Larus glaucescens) in a heavily disturbed region of the northeast Pacific to ask whether diets of this generalist forager changed in response to shifts in food availability over 150 years, and whether any detected change might explain long-term trends in gull abundance. Sampled feathers came from birds collected between 1860 and 2009 at nesting colonies in the Salish Sea, a transboundary marine system adjacent to Washington, USA and British Columbia, Canada. To determine whether temporal trends in stable isotope ratios might simply reflect changes to baseline environmental values, we also analysed muscle tissue from forage fishes collected in the same region over a multidecadal timeframe. Values of δ13C and δ15N declined since 1860 in both subadult and adult gulls ( δ13C, ~ 2-6‰; δ15N, ~4-5‰), indicating that their diet has become less marine over time, and that birds now feed at a lower trophic level than previously. Conversely, forage fish δ13C and δ15N values showed no trends, supporting our conclusion that gull feather values were indicative of declines in marine food availability rather than of baseline environmental change. Gradual declines in feather isotope values are consistent with trends predicted had gulls consumed less fish over time, but were equivocal with respect to whether gulls had switched to a more garbage-based diet, or one comprising marine invertebrates. Nevertheless, our results suggest a long-term decrease in diet quality linked to declining fish abundance or other anthropogenic influences, and may help to explain regional population declines in this species and other piscivores. [ABSTRACT FROM AUTHOR]

The article focuses on the effects of sea eagles on seabird populations. The recovery of sea eagle populations of the Haliaeetus (H.) spp. such as the Bald Eagles H. leucocephalus in North America and White-tailed Eagles H. albicilla in northern Europe is presented wherein they are thought to be approaching or at carrying capacity. Mechanisms by which seabirds and seabird numbers are affected by sea eagles are discussed such as predation, alteration of seabird behavior and facilitating predation. The recovery of sea eagle populations as reflecting a return to a more natural equilibrium, and the need for further research on its implications on seabird populations, are explored.

Seabirds integrate information about oceanic ecosystems across time and space, and are considered sensitive indicators of marine conditions. To assess whether hypothesized long-term foodweb changes such as forage fish declines may be reflected in a consumer's life history traits over time, I used meta-regression to evaluate multi-decadal changes in aspects of egg production in the glaucous-winged gull (Larus glaucescens), a common coastal bird. Study data were derived from literature searches of published papers and unpublished historical accounts, museum egg collections, and modern field studies, with inclusion criteria based on data quality and geographic area of the original study. Combined historical and modern data showed that gull egg size declined at an average of 0.04 cc y-1 from 1902 (108 y), equivalent to a decline of 5% of mean egg volume, while clutch size decreased over 48 y from a mean of 2.82 eggs per clutch in 1962 to 2.25 in 2009. There was a negative relationship between lay date and mean clutch size in a given year, with smaller clutches occurring in years where egg laying commenced later. Lay date itself advanced over time, with commencement of laying presently (2008-2010) 7 d later than in previous studies (1959-1986). This study demonstrates that glaucous-winged gull investment in egg production has declined significantly over the past ∼50-100 y, with such changes potentially contributing to recent population declines. Though gulls are generalist feeders that should readily be able to buffer themselves against food web changes, they are likely nutritionally constrained during the early breeding period, when egg production requirements are ideally met by consumption of high-quality prey such as forage fish. This study's results suggest a possible decline in the availability of such prey, and the incremental long-term impoverishment of a coastal marine ecosystem bordering one of North America's rapidly growing urban areas. [ABSTRACT FROM AUTHOR]

The article discusses a study on the interannual variation in egg neglect and incubation routine of Cerorhinca monocerata, also known as Rhinoceros Auklets, during El Niño and La Niña seasons in British Columbia from 1998 to 1999. The study procedure included keeping miniature temperature loggers in hollow plastic hobby eggs in order to achieve artificial eggs. A comparison between annual means of the number of per-burrow egg neglect events was conducted, as well a comparison of temperature sensitivity between the models of artificial eggs.

A major mid-1980s shift in ecological structure of significant portions of the Southern Ocean was partially due to the serial depletion of fish by intensive industrial fishing, rather than solely to climate factors as previously hypothesized. Over a brief period (1969–1973), several finfish stocks were on average reduced to <50%, and finally (mid-1980s) to <20%, of original size. Despite management actions, few stocks have recovered and some are still declining. Most affected species exhibit K-selected life-history patterns, and before exploitation presumably fluctuated in accordance with infrequent strong year classes, as is true of such fish elsewhere. A climate regime, the Southern Annular Mode, once oscillated between two states, but has remained in its ‘positive mode’ since the time of the fish extraction. This may have increased finfish vulnerability to exploitation. As breeding stocks decreased, we hypothesize that availability of annually produced juvenile fish fed upon by upper-level predators remained low. Correlations between predator populations and fish biomass in predator foraging areas indicate that southern elephant seal Mirounga leonina, Antarctic fur seal Arctocephalus gazella, gentoo penguin Pygoscelis papua, macaroni penguin Eudyptes chrysolphus and ‘imperial’ shag Phalacrocorax spp. – all feeding extensively on these fish, and monitored at Marion, Crozet, Kerguelen, Heard, South Georgia, South Orkney and South Shetland Islands, where fishing was concentrated – declined simultaneously during the two periods of heavy fishing. These patterns indicate the past importance of demersal fish as prey in Antarctic marine systems, but determining these interactions’ ecological mechanisms may now be impossible. [ABSTRACT FROM AUTHOR]

Presents information on a study which discussed the predation of rhinoceros auklet eggs by peromyscus. Monitoring of the rhinoceros auklet burrows; Egg predation by herbivorous voles; Conclusion.

We conducted a multi-year (1999-2001) radio telemetry study to determine patterns of colony attendance among breeding Cassin's Auklets Ptychoramphus aleuticus during the chick-rearing period on Triangle Island in British Columbia, Canada. A total of 1 625 detections were obtained for 80 individual birds (24-28 birds per year), each detected 20.3 times on average. We found that colony attendance (arrival times, departure times, in-burrow shift duration) and foraging trip duration (i.e., time away from the colony) were remarkably synchronous among individuals and years. On average, birds arrived in a pulse after darkness, with 67% of returns between 23h15 and 00h15 and a peak (22% of all returns) between 23h30 and 23h45. Birds departed synchronously en masse before sunrise, with 86% of departures between 03h15 and 04h15 and a peak (38% of all departures) between 03h45 and 04h00. Overall, parents visited the colony every 19.8 hours (median) and stayed for roughly four hours during the chick-rearing period. At the beginning of the season, female foraging trip duration was longer than that of males, though this decreased with day of year, suggesting that females may aim to recover condition immediately following egg production via increased foraging time. Most breeders routinely visited the colony every night despite the risk posed by avian predators. Understanding patterns of colony attendance is important, given changing ocean conditions and prey availability in the vicinity of the world's largest colony for this species. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article “Behind the Eco-Label, a Debate Over Antarctic Toothfish,” by E. Stokstad in the September 24, 2010 issue.

A letter to the editor is presented in response to the paper "A Global Map of Human Impact on Marine Ecosystems," by B. S. Halpern and colleagues in the February 15, 2008 issue.

We review the precautionary approach to fisheries management, propose a framework that will allow a systematic assessment of insufficient precaution and provide an illustration using an Antarctic fishery. For a single-species fishery, our framework includes five attributes: (1) limit reference points that recognize gaps in our understanding of the dynamics of the species; (2) accurate measures of population size; (3) ability to detect population changes quickly enough to arrest unwanted declines; (4) adequate understanding of ecosystem dynamics to avoid adverse indirect effects; and (5) assessment of the first four elements by a sufficiently impartial group of scientists. We argue that one or more of these elements frequently fail to be present in the management of many fisheries. Structural uncertainties, which characterize almost all fisheries models, call for higher limit points than those commonly used. A detailed look into the five elements and associated uncertainties is presented for the fishery on the Antarctic toothfish in the Ross Sea ( FAO/ CCAMLR Area 88.1, 88.2), for which management was recently described as 'highly precautionary'. In spite of having features that make the Ross Sea fishery ideal for the application of the precautionary approach, gaps in our knowledge and failure to acknowledge these gaps mean that current regulation falls short of being sufficiently precautionary. We propose some possible remedies. [ABSTRACT FROM AUTHOR]

The ocean provides food, economic activity, and cultural value for a large proportion of humanity. Our knowledge of marine ecosystems lags behind that of terrestrial ecosystems, limiting effective protection of marine resources. We describe the outcome of 2 workshops in 2011 and 2012 to establish a list of important questions, which, if answered, would substantially improve our ability to conserve and manage the world's marine resources. Participants included individuals from academia, government, and nongovernment organizations with broad experience across disciplines, marine ecosystems, and countries that vary in levels of development. Contributors from the fields of science, conservation, industry, and government submitted questions to our workshops, which we distilled into a list of priority research questions. Through this process, we identified 71 key questions. We grouped these into 8 subject categories, each pertaining to a broad component of marine conservation: fisheries, climate change, other anthropogenic threats, ecosystems, marine citizenship, policy, societal and cultural considerations, and scientific enterprise. Our questions address many issues that are specific to marine conservation, and will serve as a road map to funders and researchers to develop programs that can greatly benefit marine conservation. Setenta y Un Preguntas Importantes para la Conservación de la Biodiversidad Marina [ABSTRACT FROM AUTHOR]

To address the ongoing global biodiversity crisis, conservation approaches must be underpinned by robust information. Canada is uniquely positioned to contribute to meeting global biodiversity targets, with some of the world's largest remaining intact ecosystems, and a commitment to co-application of Indigenous ways of knowing alongside scientific, socioeconomic, and other approaches. We elicited input from experts across a range of disciplines to identify the key information needed to advance policy and management actions to conserve biodiversity in Canada. Experts concluded that, in many cases, a lack of information is not the major barrier to biodiversity conservation; instead, mechanisms to translate information into action are most urgently needed. Recognizing multiple ways of knowing, especially Indigenous knowledge systems, will be critical to support the transformative change needed to conserve biodiversity at a national scale. Collaboration among natural, social and data scientists can facilitate social change and biodiversity information management. Experts identified 50 priority information needs which emphasize the importance of (i) reviewing policies and actions and disseminating lessons learned from successes and failures; (ii) better understanding mechanisms to build public support; (iii) improving, in specific instances, understanding of the status and trends of habitats, species, ecosystems, and threats for planning and management; and (iv) mobilizing biodiversity information. Through the Convention on Biological Diversity, the global community has resolved to "live in harmony with nature"; through our Canadian case-study, we conclude that the most pressing need to address this resolution is an improved understanding of how to move from conservation knowledge to conservation action. • Experts listed 50 key needs to transform biodiversity conservation in Canada. • Translating information into action is often more urgent than collecting new data. • Creating space for Indigenous knowledge systems is critical for success. • Improving policy and building public support requires a transdisciplinary approach. • Some key monitoring data are still required, where the gaps are impeding action. [ABSTRACT FROM AUTHOR]