Seabird Monitoring Research Articles

Monitoring the Atlantic Puffin Fratercula arctica, Common Guillemot Uria aalge and Black-legged Kittiwake Rissa tridactyla breeding populations on Hornøya, northeast Norway, 1980-2000

The breeding populations of Atlantic Puffins Fratercula arctica, Common Guillemots Uria aalge and Black-legged Kittiwakes Rissa tridactyla have been monitored on Hornøya, East Finnmark since 1980 as part of the Norwegian seabird monitoring programme. Whereas numbers of Puffin burrows in plots monitored in 1981 - 1993 increased at a rate of 2.6% per year, there was no subsequent trend in counts made in a new scheme of circular plots started in 1990. Numbers of Common Guillemots collapsed between 1985 - 1987 but have since increased in all plots at a rate of 11.6% per year. Kittiwake numbers dropped significantly (1.5% per year) between 1980 - 1994, but stabilised between 1994 - 2000. Suggestions are made for improvements to the monitoring scheme to overcome inconsistencies in changes in numbers between plots (e.g. of Kittiwakes), to increase the sensitivity of the counts and for additions to help explain why any changes in the populations occur.

An ecologically sound and participatory monitoring network for pan-Arctic seabirds.

In a warming Arctic, circumpolar long-term monitoring programs are key to advancing ecological knowledge and informing environmental policies. Calls for better involvement of Arctic peoples in all stages of the monitoring process are widespread, although such transformation of Arctic science is still in its infancy. Seabirds stand out as ecological sentinels of environmental changes, and priority has been given to implement the Circumpolar Seabird Monitoring Plan (CSMP). We assessed the representativeness of a pan-Arctic seabird monitoring network focused on the black-legged kittiwake (Rissa tridactyla) by comparing the distribution of environmental variables for all known versus monitored colonies. We found that with respect to its spatiotemporal coverage, this monitoring network does not fully embrace current and future environmental gradients. To improve the current scheme, we designed a method to identify colonies whose inclusion in the monitoring network will improve its ecological representativeness, limit logistical constraints, and improve involvement of Arctic peoples. We thereby highlight that inclusion of study sites in the Bering Sea, Siberia, western Russia, northern Norway, and southeastern Greenland could improve the current monitoring network and that their proximity to local populations might allow increased involvement of local communities. Our framework can be applied to improve existing monitoring networks in other ecoregions and sociological contexts.

Monitoring Canadian Arctic seabirds at the Prince Leopold Island Field Station, 1975–2023

The research station at Prince Leopold Island (PLI), initiated in 1975, was the first seabird monitoring site created in the Canadian Arctic. The island supports 150 000 breeding pairs of seabirds, principally thick-billed murres ( Uria lomvia Linnaeus 1758), black-legged kittiwakes ( Rissa tridactyla Linnaeus 1758) and northern fulmars ( Fulmarus glacialis Linnaeus 1761), along with ∼70 pairs of glaucous gulls ( Larus hyperboreus Gunnerus 1767) and several thousand black guillemots ( Cepphus grylle Linnaeus 1758). Baseline observations of seabird breeding biology were made during 1975–1977. Subsequent monitoring has taken place in 22 of the 47 seasons, with work during 2001–2003 replicating the original baseline studies. Population trends of breeding seabirds have shown kittiwakes (sharply) and murres (gradually) increasing, while gulls (definitely) and fulmars (likely) have declined. The most striking scientific findings from PLI were related to the effect of annual ice break-up on seabird phenology, clutch size, and reproductive success. For contaminant research, PLI has become one of the core monitoring sites in Canada and internationally, documenting dramatic changes in concentrations of various contaminants in the Arctic marine environment. Given the international impact of research and monitoring at PLI for almost five decades, the continuation of seabird research at PLI, the most important seabird colony in the Canadian Arctic, is essential.

Machine and deep learning approaches to understand and predict habitat suitability for seabird breeding.

The way animals select their breeding habitat may have great impacts on individual fitness. This complex process depends on the integration of information on various environmental factors, over a wide range of spatiotemporal scales. For seabirds, breeding habitat selection integrates both land and sea features over several spatial scales. Seabirds explore these features prior to breeding, assessing habitats' quality. However, the information-gathering and decision-making process by seabirds when choosing a breeding habitat remains poorly understood. We compiled 49 historical records of larids colonies in Cuba from 1980 to 2020. Then, we predicted potentially suitable breeding sites for larids and assessed their breeding macrohabitat selection, using deep and machine learning algorithms respectively. Using a convolutional neural network and Landsat satellite images we predicted the suitability for nesting of non-monitored sites of this archipelago. Furthermore, we assessed the relative contribution of 18 land- and marine-based environmental covariates describing macrohabitats at three spatial scales (i.e. 10, 50 and 100 km) using random forests. Convolutional neural network exhibited good performance at training, validation and test (F1-scores >85%). Sites with higher habitat suitability (p > .75) covered 20.3% of the predicting area. Larids breeding macrohabitats were sites relatively close to main islands, featuring sparse vegetation cover and high chlorophyll-a concentration at sea in 50 and 100 km around colonies. Lower sea surface temperature at larger spatial scales was determinant to distinguish the breeding from non-breeding sites. A more comprehensive understanding of the seabird breeding macrohabitats selection can be reached from the complementary use of convolutional neural networks and random forest models. Our analysis provides crucial knowledge in tropical regions that lack complete and regular monitoring of seabirds' breeding sites.

Adélie penguins north and east of the ‘Adélie gap’ continue to thrive in the face of dramatic declines elsewhere in the Antarctic Peninsula region

While population declines among Adélie penguins and population increases among gentoo penguins on the Western Antarctic Peninsula are well established, the logistical challenges of operating in the sea ice-heavy northern tip of the Antarctic Peninsula have prohibited reliable monitoring of seabirds in this region. Here we describe the findings of an expedition to the northern and eastern sides of the Antarctic Peninsula—a region at the nexus of two proposed Marine Protected Areas—to investigate the distribution and abundance of penguins in this region. We discovered several previously undocumented penguin colonies, completed direct surveys of three colonies initially discovered in satellite imagery, and re-surveyed several colonies last surveyed more than a decade ago. Whereas our expectation had been that the Peninsula itself would divide the areas undergoing ecological transition and the apparently more stable Weddell Sea region, our findings suggest that the actual transition zone lies in the so-called "Adélie gap," a 400-km stretch of coastline in which Adélies are notably absent. Our findings suggest that the region north and east of this gap represents a distinct ecoregion whose dynamics stand in sharp contrast to surrounding areas and is likely to be impacted by future conservation measures.

Accessible ecophysiological tools for seabird conservation

AbstractSeabirds are the most endangered avian taxa on Earth, with over a third of species globally threatened. To help slow their decline, conservation physiology seeks to determine how seabird responses to climatic and anthropogenic threats influence demographic processes, but it is not widely utilized in monitoring.A wide variety of metrics and methods are available to the conservation practitioner; thus, the correct method selection is paramount. This is a review of physiological tools to assess both individual and population health in seabirds, outlining which tools could be accessible enough to incorporate into conservation management strategies to increase the efficacy and range of population monitoring.Ultimately, the cost and expertise required limits the use of some tools in a community‐based management context, but they are useful in academic research in collaboration with conservation projects to generate data to inform management strategies for threatened species.The value of the data available from particular tools is weighed against the invasiveness of the methodology to assess the practicality of incorporating physiological tools into routine seabird monitoring programmes.A broader application of conservation physiology tools in a monitoring context could help manage threatened species; this paper summarizes a set of physiological variables from minimally invasive samples that have potential to assist in monitoring population health for seabird conservation. The full potential of these physiological tools is yet to be realized in seabirds.

Drones and deep learning produce accurate and efficient monitoring of large-scale seabird colonies

AbstractPopulation monitoring of colonial seabirds is often complicated by the large size of colonies, remote locations, and close inter- and intra-species aggregation. While drones have been successfully used to monitor large inaccessible colonies, the vast amount of imagery collected introduces a data analysis bottleneck. Convolutional neural networks (CNN) are evolving as a prominent means for object detection and can be applied to drone imagery for population monitoring. In this study, we explored the use of these technologies to increase capabilities for seabird monitoring by using CNNs to detect and enumerate Black-browed Albatrosses (Thalassarche melanophris) and Southern Rockhopper Penguins (Eudyptes c. chrysocome) at one of their largest breeding colonies, the Falkland (Malvinas) Islands. Our results showed that these techniques have great potential for seabird monitoring at significant and spatially complex colonies, producing accuracies of correctly detecting and counting birds at 97.66% (Black-browed Albatrosses) and 87.16% (Southern Rockhopper Penguins), with 90% of automated counts being within 5% of manual counts from imagery. The results of this study indicate CNN methods are a viable population assessment tool, providing opportunities to reduce manual labor, cost, and human error.

COVID-19 lockdown reveals tourists as seabird guardians

The widespread lockdowns put in place to limit the spread of the new coronavirus disease (COVID-19) offers a rare opportunity in understanding how human presence influence ecosystems. Using data from long-term seabird monitoring, we reveal a previously concealed guarding effect by tourist groups on an iconic seabird colony in the Baltic Sea. The absence of tourists in 2020 lead to a sevenfold increase in presence of white-tailed eagles Haliaeetus albicilla, a sevenfold increase in their disturbance of breeding common murres Uria aalge and causing 26% lower murre productivity than the long-term average. Eagles did not prey on murres, but their frequent disturbances delayed egg laying and facilitated egg predation from herring gulls Larus argentatus and hooded crows Corvus cornix. Based on our findings, we suggest that human presence could be used as a strategic measure in guarding seabird colonies, and that a social-ecological systems perspective is vital for long-term success in protected area management.

Teaching old dogs and young dogs new tricks: canine scent detection for seabird monitoring

Dogs Canis familiaris have been domesticated for over 11,000 years and have been trained to perform a vast array of tasks. Scent dogs are routinely used to detect elusive animals of conservation concern as well as the presence of invasive nonnative predators. However, a recent review of studies on scent dogs for nature conservation found few peer-reviewed papers on detection of seabirds, and we suggest the potential of scent dogs for seabird monitoring is currently under-utilised. To stimulate wider consideration of the use of scent dogs for seabird monitoring we: (i) document the training, testing and performance of a one-year old Golden Retriever, to detect scent from European Storm Petrels Hydrobates pelagicus, and to differentiate between scent of European Storm Petrels and Manx Shearwaters Puffinus puffinus, and (ii) report on the field performance of a 12-year old Border Collie to detect Manx Shearwaters breeding in natural nest burrows and artificial nest boxes. We show that these individual dogs had a high success rate in locating hidden seabird targets by scent in experimental and field settings and we highlight some of the set-backs encountered during the training process, and their solutions. We show that the detection of occupied Manx Shearwater burrows is dependent on their depth and recent history of occupation. Our results highlight the potential value of scent dogs to establish the presence of particular seabird species at sites where breeding status is currently uncertain, and to map the extent of occupied areas. Further work is needed to validate the use of scent dogs to determine seabird breeding density in real-world situations, where detection probability may be influenced by nest site characteristics and breeding density. We stress the need to involve professionals in the selection, training and testing of scent dogs.

해상풍력 발전단지 주변 해역 해양보호생물 영향평가 현황 및 개선방안 : 해양포유류 및 바닷새 사례 중심

In this study, we assessed the environmental impact on marine endangered species, especially marine mammals and seabirds around offshore wind energy plant in Jeju Island and West-south coastal area during 2014-2020. To reduce fatalities of marine endangered species from noise, vibration and collision around offshore wind energy, we suggest below. First, we have to add the variable of assessment such as monitoring of marine mammals and seabirds. Second, we have to prepare the scientific monitoring platform such as high-tech vessel and flight control system. Third, we have to adopt the simulation model for seabird collision to wind energy blade.

Applications of digital imaging and analysis in seabird monitoring and research

Rapid advances in digital imaging technology offer efficient and cost‐effective methods for measuring seabird abundance, breeding success, phenology, survival and diet. These methods can facilitate understanding of long‐term population trends, and the design and implementation of successful conservation strategies. This paper reviews the suitability of satellites, manned aircraft, unmanned aerial vehicles (UAVs), and fixed‐position, handheld and animal‐borne cameras for recording digital photographs and videos used to measure seabird demographic and behavioural parameters. It considers the disturbance impacts, accuracy of results obtained, cost‐effectiveness and scale of monitoring possible compared with ‘traditional’ fieldworker methods. Given the ease of collecting large amounts of imagery, image processing is an important step in realizing the potential of this technology. The effectiveness of manual, semi‐automated and automated image processing is also reviewed. Satellites, manned aircraft and UAVs have most commonly been used for population counts. Spatial resolution is lowest in satellites, limiting monitoring to large species and those with obvious signs of presence, such as penguins. Conversely, UAVs have the highest spatial resolution, which has allowed fine‐scale measurements of foraging behaviour. Time‐lapse cameras are more cost‐effective for collecting time‐series data such as breeding success and phenology, as human visits are only required infrequently for maintenance. However, the colony of interest must be observable from a single vantage point. Handheld, animal‐borne and motion‐triggered cameras have fewer cost‐effective uses but have provided information on seabird diet, foraging behaviour and nest predation. The last of these has been important for understanding the impact of invasive mammals on seabird breeding success. Advances in automated image analysis are increasing the suitability of digital photography and videography to facilitate and/or replace traditional seabird monitoring methods. Machine‐learning algorithms, such asPengbot, have allowed rapid identification of birds, although training requires thousands of pre‐annotated photographs. Digital imaging has considerable potential in seabird monitoring, provided that appropriate choices are available for both image capture technology and image processing. These technologies offer opportunities to collect data in remote locations and increase the number of sites monitored. The potential to include such solutions in seabird monitoring and research will develop as the technology evolves, which will be of benefit given funding challenges in monitoring and conservation.

Comparing imaging, acoustics, and radar to monitor Leach's storm-petrel colonies.

Seabirds are integral components of marine ecosystems and, with many populations globally threatened, there is a critical need for effective and scalable seabird monitoring strategies. Many seabird species nest in burrows, which can make traditional monitoring methods costly, infeasible, or damaging to nesting habitats. Traditional burrow occupancy surveys, where possible, can occur infrequently and therefore lead to an incomplete understanding of population trends. For example, in Oregon, during the last three decades there have been large changes in the abundance of Leach’s storm-petrels (Hydrobates leucorhoa), which included drastic declines at some colonies. Unfortunately, traditional monitoring failed to capture the timing and magnitude of change, limiting managers’ ability to determine causes of the decline and curtailing management options. New, easily repeatable methods of quantifying relative abundance are needed. For this study, we tested three methods of remote monitoring: passive acoustic monitoring, time-lapse cameras, and radar. Abundance indices derived from acoustics and imagery: call rates, acoustic energy, and counts were significantly related to traditional estimates of burrow occupancy of Leach’s storm-petrels. Due to sampling limitations, we were unable to compare radar to burrow occupancy. Image counts were significantly correlated with all other indices, including radar, while indices derived from acoustics and radar were not correlated. Acoustic data likely reflect different aspects of the population and hold the potential for the further development of indices to disentangle phenology, attendance of breeding birds, and reproductive success. We found that image counts are comparable with standard methods (e.g., radar) in producing annual abundance indices. We recommend that managers consider a sampling scheme that incorporates both acoustics and imaging, but for sites inaccessible to humans, radar remains the sole option. Implementation of acoustic and camera based monitoring programs will provide much needed information for a vulnerable group of seabirds.

Aves marinas varadas en la bahía de Coquimbo, norte de Chile: ¿Qué especies y cuántas mueren?

El monitoreo de las aves varadas en las playas puede proporcionar información sobre sus causas de muerte, tales como la captura incidental en actividades de pesca o derrames de petróleo. Durante un año fue monitoreada mensualmente la Bahía de Coquimbo, norte de Chile para cuantificar el número de aves marinas varadas. Se encontraron 395 aves marinas muertas de las cuales 382 fueron identificadas y agrupadas en 21 especies. Las especies más abundantes fueron los piqueros con 115 individuos (30%), el cormorán guanay con 83 individuos (22%) y la gaviota dominicana con 65 individuos (17%). Las especies más abundantes y frecuentes fueron las que anidan en el Sistema Costero de Coquimbo. La mortalidad afecta principalmente a las aves marinas que se alimentan de la anchoveta, que es el principal recurso objetivo de la pesca con redes de cerco. Se sugiere que la mortalidad incidental causada por la pesca es crónica y relativamente constante durante el año. Se requiere un programa de monitoreo a largo plazo para mejorar la estimación de la mortalidad y los factores que influyen en la interacción de las aves marinas con las artes de pesca.

Weather effect on widely distributed seabirds through migration flyways: a case study with the Northern Gannet Morus bassanus in the Bay of Biscay

ABSTRACTCapsule: Northern Gannet Morus bassanus counts obtained from a coastal monitoring network in northern Spain were highly determined by wind conditions.Aims: To determine how external factors including weather conditions affect seabird counts in a land-based seabird monitoring project (Red de observación de Aves y Mamíferos marinos, RAM project; Seabird & Marine Mammal Observation Network).Methods: Seabird counts were obtained from four study capes situated in the southeastern part of the Bay of Biscay in northern Spain. Counts were conducted on a monthly-basis for a period of 3 hours starting at dawn on each sampling day. Data used here were compiled over a 10-year period (2006–15).Results: Northern Gannet numbers were chiefly influenced by meteorological conditions at a local spatial scale. Northwesterly winds were found to positively influence gannet abundance, whereas high relative humidity caused a decrease in abundance. Moreover, gannets were more abundant during the non-breeding period as compared to breeding period.Conclusion: We recommend considering the effect of the wind and relative humidity on land-based seabird counts in the Bay of Biscay when handling data from the RAM protocol in order to avoid biases and misinterpretation of data. Since seabirds approach the coast during harsh weather conditions, the RAM protocol should be improved in order to better account for the distance at which the birds are seen.

Seabirds as regional biomonitors of legacy toxicants on an urbanized coastline

Seabirds are often cited as sentinels of the marine environment, but are rarely used in traditional ocean and coastal contaminant monitoring. Four classes of persistent organic pollutants (POPs, n=68) and three trace elements (mercury, selenium, and arsenic) were measured in the eggs of California least terns (Sterna antillarum browni), caspian terns (Hydroprogne caspia), double-crested cormorants (Phalacrocorax auritus), and western gulls (Larus occidentalis) that nest in the Southern California Bight. Building on a periodic five year regional monitoring program, we measured contaminant exposure and assessed the utility of seabirds as regional contaminant biomonitors. We found that the eggs of larger, more piscivorous species generally had the highest concentrations of POPs and trace elements while California least terns had the lowest concentrations, except for mercury which was higher in least terns. As expected, DDT concentrations were elevated near the Palos Verdes Superfund site. However, we also detected a previously unknown latitudinal pattern in PBDE concentrations in least terns. POP congener profiles also confirmed differences in contamination in urban least tern colonies closest to urban centers. Though toxicants were at detectable levels across species and sites, concentrations were below those known to cause adverse effects in avian taxa and are steady or declining compared to previous studies in this region. Our results suggest that regional seabird monitoring can inform site-specific remediation and support management and protection of regionally-threatened wildlife and coastal systems. Integration of seabird contaminant data with traditional sediment, water, bivalve and fish monitoring is needed to further our understanding of exposure pathways and food web contaminant transfer.

Hugh Boyd, CM (1925–2016)

Hugh Boyd, <scp>CM</scp> (1925–2016)

Monitoring Wildlife and their Habitats in the Southern Ocean and around Indian Research Stations in Antarctica

Antarctica and its surrounding ocean are at the centre stage of rapid and extreme environmental events due to prevailing global climate change, which in turn necessitates long-term monitoring of wildlife and their habitats in this region. Systematic monitoring of seabirds and marine mammals were carried out during five austral summers (2008-09, 2009-10, 2013-14, 2014-15 and 2015-16). Vessel-based surveys for pelagic seabirds in the southern Indian Ocean, aerial surveys for seals and penguins and field surveys for locating nesting sites of Antarctic birds were conducted at Indian area of operation in Antarctica. Forty-nine species of seabirds were observed during the vessel-based surveys. Species richness peaked in the mid-latitudes but species abundances increased along higher latitudes towards Antarctica. Planktivorous species in the lower latitudes were replaced by mixed prey dependent species in the higher latitudes. Aerial surveys recorded a total of four species of seals viz. Weddell seal, Crabeater seal, Leopard seal and Ross seal and two penguin species viz. Emperor penguin and Adelie penguin. Out of 15 islands in Larsemann hills that were surveyed on-foot, the presence of nesting sites of seabirds is reported from 13 islands. The preliminary results from our study provide the baseline data for ecologically important species within Indian area of operation in Antarctica and will help design future research activities.

Visualising the aspect-dependent radar cross section of seabirds over a tidal energy test site using a commercial marine radar system

The long-term monitoring of seabirds around proposed marine renewable energy (MRE) sites is vital to assess the large-scale and long-term environmental impacts of MRE installations. Marine radar could be a valuable tool to augment traditional seabird surveys but the problem of aspect dependency of the generic radar cross section (RCS) of live birds in flight must be understood before radar data is correctly interpreted. A marine radar multiple target tracking algorithm (‘GANNET’) was applied to data from an un-calibrated, horizontally polarised, 10kW X-band marine radar sited at the European Marine Energy Centre (EMEC) tidal renewable energy test site, Scotland U.K. From 24days of data over 1.84million target readings were recorded. For each target reading the radar aspect angle (bearing of radar beam incident on target), range and non-dimensional echo magnitude were derived allowing a view to be generated of the variation of echo magnitude with aspect angle for all tracked targets. The resulting polar diagram shows a significant change in echo magnitude with range between side-on and head/tail-on aspects indicating a large contribution of the RCS from the wings of birds in flight. The species-unspecific detectability of seabirds, especially at long range, is found to be strongly dependent on aspect angle. This has direct implications for the use of marine radar equipment for avian monitoring at proposed and active marine energy sites and must be taken into account if data from these radars are to be used to augment traditional bird abundance and area use surveys conducted by human observers.

Monitoring the breeding success of Common Guillemots Uria aalge: the value of multiple plots

Results from seabird monitoring programmes are increasingly being used to assess the state of the marine environment, but data are time consuming to collect. We used monitoring data from a colony of Common Guillemots Uria aalge in the North Sea to determine whether temporal changes in breeding success over a 34- year period were reflected in six consistently monitored plots and if individual plots showed significant differences in breeding success. Annual mean breeding success showed a four-fold difference over the study period varying from 0.261 to 0.848 young fledging per pair laying. Although the annual pattern of change was broadly reflected in all six monitoring plots there were significant differences in annual breeding success and changes in breeding success over time among the plots. Monitoring any single plot thus gave an approximate indication of the overall patterns of change over time, including periods when breeding success was reduced. However, significant among plot differences indicated that at least at this colony, robustness of colony level estimates of breeding success and changes over time were improved by monitoring multiple plots.

AUTOMATIC SEA BIRD DETECTION FROM HIGH RESOLUTION AERIAL IMAGERY

Abstract. Great efforts are presently taken in the scientific community to develop computerized and (fully) automated image processing methods allowing for an efficient and automatic monitoring of sea birds and marine mammals in ever-growing amounts of aerial imagery. Currently the major part of the processing, however, is still conducted by especially trained professionals, visually examining the images and detecting and classifying the requested subjects. This is a very tedious task, particularly when the rate of void images regularly exceeds the mark of 90%. In the content of this contribution we will present our work aiming to support the processing of aerial images by modern methods from the field of image processing. We will especially focus on the combination of local, region-based feature detection and piecewise global image segmentation for automatic detection of different sea bird species. Large image dimensions resulting from the use of medium and large-format digital cameras in aerial surveys inhibit the applicability of image processing methods based on global operations. In order to efficiently handle those image sizes and to nevertheless take advantage of globally operating segmentation algorithms, we will describe the combined usage of a simple performant feature detector based on local operations on the original image with a complex global segmentation algorithm operating on extracted sub-images. The resulting exact segmentation of possible candidates then serves as a basis for the determination of feature vectors for subsequent elimination of false candidates and for classification tasks.