Cliff-nesting Seabirds Research Articles

Monitoring colonial cliff-nesting seabirds in the Canadian Arctic: The Coats Island field station

The Coats Island field station in northern Hudson Bay, Canada, was established by the Canadian Wildlife Service in 1984 to monitor the thick-billed murre ( Uria lomvia, akpa, [Formula: see text]) population in the context of harvest management and federal responsibilities under the Migratory Birds Convention Act. The long-term monitoring program has continued annually for 34 of the last 39 years, making it the most frequently monitored seabird colony in the Canadian Arctic. In the 1990s, the focus of efforts at the site shifted from population monitoring and harvest management to long-term monitoring of murres as an indicator of environmental change. In addition to informing harvest management of murres in Canada, long-term monitoring and research at Coats Island have helped to establish thick-billed murres as an indicator species for Arctic seabirds, identified major shifts in the marine prey communities of Hudson Bay, enabled the assessment of international agreements on reducing contaminants in Arctic wildlife, and improved the understanding of the effects of climate change on Arctic marine birds. Coats Island has developed into an essential research site for all aspects of murre ecology and served as a training site for new generations of Arctic ecologists.

Surveying cliff-nesting seabirds with unoccupied aircraft systems in the Gulf of Alaska

Drones, or unoccupied aircraft systems (UAS), can transform the way scientific information on wildlife populations is collected. UAS surveys produce accurate estimates of ground-nesting seabirds and a variety of waterbirds, but few studies have examined the trade-offs of this methodology for counting cliff-nesting seabirds. In this study, we examined how different UAS survey parameters might influence seabird counts for population monitoring and assessed behavioral responses to aerial surveys for three sub-Arctic seabird taxa in the Gulf of Alaska: common murres (Uria aalge), black-legged kittiwakes (Rissa tridactyla), and pelagic and double-crested cormorants (Phalacrocorax pelagicus and Phalacrocorax auritus). We flew two commercially available models of UAS in planned approaches at different speeds and distances from colonies during incubation and chick-rearing periods. We compared counts from UAS-derived images with those from vessel-based photography and assessed video recordings of individual birds’ behaviors for evidence of disturbance during UAS operations and control phases. Count estimates from UAS images were similar to or higher than those from conventional vessel-based images, and UAS were particularly effective at photographing birds at sites with high cliff walls or complex topography. We observed no significant behavioral responses to the UAS by murres or cormorants, but we did observe flushing by black-legged kittiwakes during UAS flights; most of these birds were not incubating or brooding. At both the colony and individual level, we observed slightly greater responses to the smaller UAS platform and closer approaches. These results inform both species specific and general best practices for research and recreational usage of UAS near cliff-nesting seabird colonies.

Small-scale natural landscape features and seabird nesting sites: the importance of geodiversity for conservation

Landscape geodiversity, and in particular small natural features (SNF), are crucial components of habitat suitability for many threatened species. Rocky cliffs at the sea-continent interface present complex small-scale geomorphologies which are exploited by nesting seabirds. Elucidation of the relation between nest-site geomorphology and species preference in cliff-nesting seabirds. Evaluation of the potential of cliff-face SNF as seabird conservation tools. Nest site geomorphological characteristics of four Atlantic (Brittany, France) cliff-dwelling seabirds (Razorbill, Guillemot, Fulmar, and Kittiwake) were categorized, and scored for degree of enclosure. Of the 1048 nest sites examined, the greatest species overlap in location was the mid-region of the cliff face: Fulmar was concentrated in the upper half of the cliff, while Kittiwake showed the most extended vertical distribution. A distinct trend was evident with respect to ceiling presence and size: Razorbill + Kittiwake > Guillemot > Fulmar. Clear trends were also evident in ceiling inclination, ledge size, and side wall presence and inclination. A distinct ‘degree of enclosure’ hierarchy was documented, consolidated with the addition of sympatric species known for their extreme preferences: Atlantic Gannets and Guillemots at the extreme ‘open’ end, and Puffins and Storm Petrels at the extreme ‘closed’ end. Some plasticity in site choice was observed, probably corresponding to sub-optimal default choices. Despite some plasticity, both vertical level and enclosure characteristics are associated with particular seabird species. Given the importance of nesting sites to seabird reproduction, the identification and conservation of these SNF constitute crucial conservation objectives.

Seabird species vary in behavioural response to drone census

Unmanned aerial vehicles (UAVs) provide an opportunity to rapidly census wildlife in remote areas while removing some of the hazards. However, wildlife may respond negatively to the UAVs, thereby skewing counts. We surveyed four species of Arctic cliff-nesting seabirds (glaucous gull Larus hyperboreus, Iceland gull Larus glaucoides, common murre Uria aalge and thick-billed murre Uria lomvia) using a UAV and compared censusing techniques to ground photography. An average of 8.5% of murres flew off in response to the UAV, but >99% of those birds were non-breeders. We were unable to detect any impact of the UAV on breeding success of murres, except at a site where aerial predators were abundant and several birds lost their eggs to predators following UAV flights. Furthermore, we found little evidence for habituation by murres to the UAV. Most gulls flew off in response to the UAV, but returned to the nest within five minutes. Counts of gull nests and adults were similar between UAV and ground photography, however the UAV detected up to 52.4% more chicks because chicks were camouflaged and invisible to ground observers. UAVs provide a less hazardous and potentially more accurate method for surveying wildlife. We provide some simple recommendations for their use.

European Seabirds Show Stable Contemporary Biogeography

Abstract The geographic distribution and populations of cliff-nesting seabirds are essential elements in the assessment of their ecological roles and status. Here, a geographic mapping approach was used to visualize the biogeography of European seabirds. This approach was conducted at two temporally separated time intervals: 2004–2010 was compared to 1982–1988. Three biogeographic regions were identified: Arctic, Boreal and Ibero-Atlantic. The data show that species richness has remained stable over the approximately 20-year interval, as have, in general, population numbers and geographic distribution. Such stability, compared to recent declining trends worldwide, may be due to earlier human-driven declines in the European Atlantic, followed by effective conservation measures for the remaining populations. The species richness of cliff-nesting seabirds may not be principally determined by island area and distance from a large land mass, but rather by the extent of vertical cliff facade and distance from f...

Cliff-nesting seabirds influence production and sediment chemistry of lakes situated above their colony

Seabirds that congregate in large numbers during the breeding season concentrate marine-derived nutrients to their terrestrial nesting sites, and these nutrients disperse and enhance production in nearby terrestrial, freshwater and marine ecosystems. In the Canadian Arctic, large seabird colonies (>100,000 breeding pairs) nest on cliff faces that drain directly in the ocean, ultimately returning the nutrients back to the marine environment from which they were derived. However, strong winds blowing up cliff faces could transport nutrients up in elevation and onto surrounding terrestrial and aquatic environments. Here, we assess the degree to which seabird nutrients and metals have been delivered to coastal lakes near Hudson Strait (Nunavut, Canada) over the past century. Three lakes located at a higher elevation and increasing distance from a thick-billed murre (Uria lomvia) colony (~400,000 breeding pairs) were sampled for surface water chemistry. In addition, algal assemblages, nitrogen isotopes, and metal/metalloids were analyzed in four dated sediment cores. Elevated nutrients and major ions, as well as an enriched δ15N signature in the sediment cores, were measured in the lake <100m from the cliff, whilst no comparable changes were recorded in lakes >1km from the seabird colony. In contrast, similar oligotrophic and benthic diatom assemblages were identified in all three lakes, suggesting that diatoms were not influenced by enhanced nutrient inputs in this Arctic environment. Chemical tracers (e.g., total mercury) and algal assemblages in the lake near the colony suggest climate warming since ~1950 was the most likely driver of limnological changes, but this effect was muted in the more distant lakes. These pronounced changes in the seabird-impacted lake suggest that, with warming air temperatures and diminished lake ice cover, longer growing seasons may allow for aquatic organisms to more fully exploit the seabird nutrient subsidies.

Use of time-lapse photography and digital image analysis to estimate breeding success of a cliff-nesting seabird

Development of new methods for obtaining basic demographic data from difficult-to-access breeding colonies and easily disturbed species is an important challenge in studies of seabirds. We describe a method that can generate data concerning annual breeding success of cliff-nesting seabirds or other colonial birds with open nests. Our method requires only a single visit to a colony every second or third year, and is based on the use of automated time-lapse photography. To test our method, we used time-lapse photos to examine the breeding success of Thick-billed Murres (Uria lomvia) in two breeding colonies in Greenland during the years 2011, 2012, and 2014. Based on the analysis of time-lapse photos, we found that hatching success during the 3 yr of our study ranged from 60% to 81%, fledging success from 89% to 95%, and breeding success from 53% to 74% (Table 1). Use of digital image analysis made it possible to differentiate between breeding and non-breeding birds and determine if and when breeding attempts failed or succeeded. The key to making our method a realistic long-term monitoring technique is the use of an automated, formal image analysis to process the thousands of photos from the time-lapse cameras and, more specifically, to reduce a large number of photos to a manageable number. Using our method, we needed 12–22 h per study plot, depending on the number of breeding sites per plot (range = 47–127) and whether it was the first or the second time the plot was analyzed, to obtain our estimates of hatching, fledging, and breeding success. This included time for data preparation, image analyses, visual inspections, and summarizing data in a spreadsheet. We found that our estimates of breeding success were comparable to those obtained by direct observation in the field. An important aspect of using time-lapse technology is to foresee potential reasons why time-lapse cameras might stop taking pictures, for example, equipment failure (camera, timer, or battery) or interference by visitors (e.g., vandalism or theft). As such, thorough testing of time-lapse systems and selecting camera locations less likely to be disturbed are most important. We believe that use of time-lapse photography in combination with digital image analysis to estimate breeding success can be useful for determining the breeding success of other cliff-nesting seabirds and, more generally, other birds that breed in colonies, especially those located in remote areas and where direct observation may disturb birds.

Modelling state uncertainty with photo series data for the estimation of breeding success in a cliff-nesting seabird

Breeding success in cliff-nesting seabirds has until now been estimated through repeated nest checks by field workers during the breeding season. The use of automatic cameras offers a method for collecting mark–recapture data that can be modelled in order to estimate productivity without making recurring inspections. This saves expense and work hours in the field and allows for more colonies to be monitored. Capture histories for Brunnich’s Guillemot Uria lomvia breeding sites in a colony on Svalbard were generated using a series of photos taken by a time-lapse camera during the breeding season. To account for state uncertainty for the offspring when only the adult could be observed on the breeding site, we applied a multievent model. We estimated egg survival, hatching success and chick survival rates by modelling state transitions. Subsequently, the estimates were used to calculate breeding success. In order to assess the performance of the model, we compared the estimates with field observations of productivity. The observed breeding success in the study plot lay within the confidence intervals of the breeding success estimated by our model. We show that automatic cameras can be used to collect data which, by the application of new modelling techniques, will provide reliable estimates of demographic parameters that are vital for research and management of cliff-nesting birds. The method presented is a very good supplement to physical examination or “manual” around-the-clock monitoring of breeding birds.

Hitting the buffers: conspecific aggression undermines benefits of colonial breeding under adverse conditions

Colonial breeding in birds is widely considered to benefit individuals through enhanced protection against predators or transfer of information about foraging sites. This view, however, is largely based on studies of seabirds carried out under favourable conditions. Recent breeding failures at many seabird colonies in the UK provide an opportunity to re-examine costs and benefits of coloniality under adverse conditions. Common guillemots Uria aalge are highly colonial cliff-nesting seabirds with very flexible parental care. Although the single chick is normally never left alone, more than 50 per cent of offspring were left unattended at a North Sea colony in 2007, apparently because poor conditions forced both parents to forage simultaneously. Contrary to expectation, unattended chicks were not killed by avian predators. Rather, although non-breeders and failed breeders sometimes provided alloparental care, unattended chicks were frequently attacked by breeding guillemots at neighbouring sites, often with fatal consequences. These results highlight a previously unsuspected trade-off between provisioning chicks and avoiding conspecific attacks, and indicate that understanding how environmental conditions affect social dynamics is crucial to interpreting costs and benefits of colonial breeding.

Impact of climate change on zooplankton communities, seabird populations and arctic terrestrial ecosystem—A scenario

Many arctic terrestrial ecosystems suffer from a permanent deficiency of nutrients. Marine birds that forage at sea and breed on land can transport organic matter from the sea to land, and thus help to initiate and sustain terrestrial ecosystems. This organic matter initiates the emergence of local tundra communities, increasing primary and secondary production and species diversity. Climate change will influence ocean circulation and the hydrologic regime, which will consequently lead to a restructuring of zooplankton communities between cold arctic waters, with a dominance of large zooplankton species, and Atlantic waters in which small species predominate. The dominance of large zooplankton favours plankton-eating seabirds, such as the little auk (Alle alle), while the presence of small zooplankton redirects the food chain to plankton-eating fish, up through to fish-eating birds (e.g., guillemots Uria sp.). Thus, in regions where the two water masses compete for dominance, such as in the Barents Sea, plankton-eating birds should dominate the avifauna in cold periods and recess in warmer periods, when fish-eaters should prevail. Therefore under future anthropogenic climate scenarios, there could be serious consequences for the structure and functioning of the terrestrial part of arctic ecosystems, due in part to changes in the arctic marine avifauna. Large colonies of plankton-eating little auks are located on mild mountain slopes, usually a few kilometres from the shore, whereas colonies of fish-eating guillemots are situated on rocky cliffs at the coast. The impact of guillemots on the terrestrial ecosystems is therefore much smaller than for little auks because of the rapid washing-out to sea of the guano deposited on the seabird cliffs. These characteristics of seabird nesting sites dramatically limit the range of occurrence of ornithogenic soils, and the accompanying flora and fauna, to locations where talus-breeding species occur. As a result of climate warming favoring the increase of ichthyiofagous cliffnesting seabirds, we can expect that large areas of ornithogenic tundra around the colonies of plankton-eating seabirds situated far from the sea may disappear, while areas of tundra in the vicinity of cliffs inhabited by fish-eating seabirds, with low total production and supporting few large herbivores, will likely increase, but only imperceptibly. This may lead to habitat fragmentation with negative consequences for populations of tundra-dependent birds and mammals, and the possibility of a substantial decrease in biodiversity of tundra plant and animal communities. r 2007 Elsevier Ltd. All rights reserved.

Systematics and Ecology of the Genus &lt;I&gt;Neossos&lt;/I&gt; (Diptera: Heleomyzidae), Nest Associates of Birds

Abstract The Nearctic genus Neossos Malloch is revised. The genus contains three species: Neossos marylandicus Malloch (type locality: Bell, MD), Neossos californicus Melander (type locality: Corona del Mar, CA), and Neossos atlanticus n. sp. (type locality: Ile Bonaventure, Quebec, Canada). All species are described and illustrated, and a key to species is provided. The male postabdomen of the genus is described in detail for the first time. All known specimens of Neossos have been collected from bird nests, and the larvae and adults are apparently closely associated with the nest material. Morphological differences between the three species of Neossos correspond to differences in avian hosts at the ordinal level, architecture of host nests, and geographic distribution. N. marylandicus is associated with cavity-nesting passerine birds in eastern North America, N. californicus with raptors in western North America, and N. atlanticus with colonial, cliff-nesting seabirds in eastern North America.

Bird Observations in Severnaya Zemlya, Siberia

Fieldwork in different parts of Severnaya Zemlya in 1985, 1991, 1992 and 1993 and aerial surveys in 1994 revealed a limited bird fauna with a total of 17 breeding species. The most numerous breeding birds are cliff-nesting seabirds, comprising little auk ( Alle alle ), 10 000-80 000 pairs; kittiwake ( Rissa tridactyla ), 5000-10 000; black guillemot ( Cepphus grylle ), 1000-5000; ivory gull ( Pagophila eburnea ), 1000-2000; and glaucous gull ( Larus hyperboreus ), 500-1000. They breed all over the archipelago, usually in rather small mixed- or single-species colonies. Arctic tern ( Sterna paradisaea ) 100-500, and herring gull ( Larus argentatus ) 1-10, breed as solitary pairs or with a few pairs together. Of tundra birds, only brent goose ( Branta bernicla ), purple sandpiper ( Calidris maritima ) and snow bunting ( Plectrophenax nivalis ) are found breeding on most of the major islands. The other tundra species--red-throated diver ( Gavia stellata ), king eider ( Somateria spectabilis ), sanderling ( Calidris alba ), Arctic skua ( Stercorarius parasiticus ), long-tailed skua ( Stercorarius longicaudus ), snowy owl ( Nyctea scandiaca ) and Lapland bunting ( Calcarius lapponicus )--breed in small numbers and in limited areas, often not every year. Of the even fewer mammal species, reindeer ( Rangifer tarandus ) occurs occasionally, while Arctic fox ( Alopex lagopus ) and collared lemming ( Dicrostonyx torquatus ) are locally common in some years. Key words: Severnaya Zemlya, high Arctic birds, breeding distribution

Colonies of Northern Fulmars and Black-legged Kittiwakes Associated with the Northeast Water Polynya, Northeast Greenland

The first census of cliff-nesting seabirds dependent on the resources of the Northeast Water polynya was carried out in 1993. We made direct counts in six known colonies of the northern fulmar ( Fulmarus glacialis ) and used a combination of direct and photo counts in one colony of black-legged kittiwakes ( Rissa tridactyla ). Glaucous gulls ( Larus hyperboreus ) occurring at these colonies were also surveyed. A total of 1887 apparently occupied fulmar sites were counted, and a subjective attempt to correct for missed sites gave a total of 2550 apparently occupied sites, in which an estimated 1475 pairs laid eggs. The cliffs at Mallemukfjeld and a neighbouring unnamed cliff held 80% of the fulmar sites. Kittiwakes nested only at Mallemukfjeld, which held 873 apparently occupied sites in which an estimated 733 pairs initiated laying. The minimum glaucous gull population present in the six fulmar colonies was estimated at 22 occupied sites. The fulmar and kittiwake colonies at the Northeast Water polynya were larger than previously assumed. We present estimates based on daily variation in colony attendance of the effort required to detect annual differences in population size. There is now a basis for evaluating any future population changes in some of the most extreme high-arctic seabird populations. Key words: northern fulmar, Fulmarus glacialis , black-legged kittiwake, Rissa tridactyla , seabirds, population monitoring, polynya, high Arctic, Greenland

Recent changes in the numbers of some cliff-nesting seabirds on the Isle of May

Recent trends in numbers of Guillemots, Razorbills and Kittiwakes as shown by whole colony counts and standardized counts of monitoring plots are described for the Isle of May, Fife. Colony totals for the 3 species were all significantly higher in 1986 than in 1969 but counts made since 1980 indicate that numbers may have reached a plateau. Whilst year-to-year changes in numbers of Guillemots in the various plots were broadly similar, there was far less consistency in the changes shown by Razorbills and particularly Kittiwakes. The trends shown by these species on the Isle of May were similar to those observed recently in other North Sea colonies. Possible factors which might influence changes in numbers of these species are discussed.

Trends of population change at colonies of cliff-nesting seabirds in the Moray Firth

SynopsisAvailable information on the sizes and locations of seabird breeding colonies in the Moray Firth is reviewed. Guillemot is the most abundant species with a population of about 149,000 individuals at thirteen main colonies. The bulk of the populations of each species occur in east Caithness. Comparison of counts made in 1969 with more recent censuses indicate substantial increases in population size in the 1970s for most species. The results of annual counts at detailed study plots in five Caithness colonies between 1980 and 1984 suggest that this trend of increase has ceased for guillemots, razorbills and kittiwakes.

A Comparsion of Nesting‐Ledges Used by Seabirds on St. George Island

Measurements of 288 nesting—ledges of six species of seabirds on St. George Island, Alaska, revealed significant interspecific differences in the size, shape, and overhang of ledges used. Typically, Red—legged Kittiwakes used ledges 1 dm deep; Northern Fulmars, Black—legged Kittiwakes, and Thick—billed Murres used ledges of an intermediate 2—4 dm depth; Red—faced Cormorants used ledges 3—6 dm deep; and Common Murres occurred singly on shallow ledges or in groups on deeper ledges. Fulmars and murres, which did not build nests, used nearly horizontal ledges exclusively; the nest—building species occurred on a wider range of slopes. Only the Red—legged Kittiwake regularly used ledges with over 50% cover by overhanging cliff within 5 dm of the ledge. Classification of the measured ledges of the cormorant, the two kittiwakes, and the Thick—billed Murre by a discriminant function analysis revealed significantly greater overlap than expected between the species pairs of cormorant with Thick—billed Murre, Black—legged with Red—legged Kittiwake, and Black—legged Kittiwake with Thick—billed Murre. Observations of 43 interspecific exchanges of nest sites during and between three breeding seasons agreed with the predictions by the discriminant analysis of overlap or lack thereof in three of four significant cases. Exchanges occurred significantly more frequently than expected between the species pairs of cormorant with Black—legged Kittiwake, cormorant with Thick—billed Murre, and Black—legged with Red—legged Kittiwake.

Detection of Annual Changes in the Numbers of Cliff-Nesting Seabirds in Orkney 1976-80

(1) This paper reports on a 5-year project set up in Mainland, Orkney, Scotland to assess annual and longer-term changes in numbers of four seabird species against a pattern of temporal variability. (2) Between five and ten standardized counts of individual guillemots Uria aalge, razorbills Alca torda, kittiwakes Rissa tridactyla and fulmars Fulmarus glacialis and apparently occupied nests and sites of kittiwakes and fulmars were made in fixed plots at five colonies in the month of June from 1976 to 1980. (3) Analyses of variance were used to test for changes in numbers between years. The method's sensitivity using five or ten counts per year was assessed by calculating the power of the two-tailed t-test for specified proportionate changes in the mean counts. (4) Between 1976 and 1980 there were significant differences between annual colony means in all the species and categories counted. Interaction of colonies with years for all categories (except kittiwake nests) indicated unidirectional change but at different rates. For kittiwake nests, interaction indicated opposing trends in the colonies. All colonies showed mean annual increases in numbers of individual guillemots, razorbills and fulmars and fulmar sites (except Costa Head). There were mean annual decreases at all colonies (except Mull Head) in numbers of kittiwake nests and individuals. (5) Five counts per year were sufficient to detect proportionate changes of +30% for guillemots and kittiwakes (nests and individuals) and fulmar (individuals). To achieve this precision for razorbills, ten counts would need to be made in a shortened sampling period. Fulmar sites were borderline, probably partly because of the subjectivity involved in defining this category.

The recent status of Monachus monachus, the Mediterranean monk seal

Mediterranean monk seals Monachus monachus (Hermann 1779) still live widely in their primaeval range around the Mediterranean and adjacent northeast Atlantic seas, but are now confined chiefly to remote cliffbound coasts and islets. Greatest numbers occur in the eastern Aegean sea. Total numbers are probably between 500 and 1000 with the population still declining. Neonates measure about 0·8 m length and weigh about 20 kg, while adults reach extreme sizes of 3m and 400 kg. The wide food spectrum of fish and cephalopods, probably reaching 5% of body weight per day as an optimum intake for adults, produces competition with fishermen. Seals damage nets and are shot, and are also caught inadvertently in various types of nets. Births extend from May to November with a peak in September. Human disturbance of reproductive sites at all seasons is believed to be seriously reducing the reproductive rate of monk seals. Efficient reproduction probably requires beaches as well as the caves mostly used at present. Individual travel can be several hundred kilometres and widespread similarity of colour patterns suggests that gene flow has not been interrupted in the past. A network of reserves is needed in existing and past habitat, which could be of value also to rare cliff-nesting sea birds. These core reserves should be totally free of human disturbance, but buffer zones are envisaged surrounding them, which could be used for viewing the animals.