Download or read book Grey Seal Halichoerus Grypus Haul out Pattern and Behavioural Response to Environmental Variables and Anthropogenic Disturbances on Puffin Island North Wales written by Claire Louise Bass and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Habitat Use Haul out Behaviour and Site Fidelity of Grey Seals Halichoerus Grypus Along the Ceredigion Marine Heritage Coast Wales written by Kate Michelle Lewis and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Description and Probable Behavioral Significance of Grey Seal Halichoerus Grypus Vocalizations written by Jack Schneider and published by . This book was released on 1974 with total page 37 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Observations of the grey seal Halichoerus grypus at North Rona in 1960 written by J.M. BOYD and published by . This book was released on 1962 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Fine scale Determinants of Female Grey Seal Halichoerus Grypus Pupping Site and Habitat Preferences at North Rona Scotland written by James Edward Stewart and published by . This book was released on 2013 with total page 231 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract:The grey seal (Halichoerus grypus) is widespread in the Northern Hemisphere and throughout its range hauls out to breed terrestrially on a variety of substrates. A major breeding site in the eastern North Atlantic is the remote island of North Rona, Scotland, which is characterised by undulating grassy terrain, with limited access to the sea, punctuated by irregularly spaced fresh to brackish water pools of variable size. Previous long term research at North Rona has suggested that the distribution of breeding females is influenced by key habitat features including proximity to pools of water and to access from the sea. Using distributional information available for the North Rona colony in conjunction with a set of ecologically relevant environmental predictors within an extensive GIS database, the ecological niche of the grey seal at North Rona was modelled using Ecological Niche Factor Analysis. This was used to determine the distribution of suitable habitat at the North Rona colony and to elucidate the environmental determinants of female pupping site, and subsequent habitat, preferences over multiple years spanning 1998-2010. The environmental predictors utilised were chosen based on the conclusions of previous research. Following the delineation of basic environmental preferences, the influence of social interactions was considered within this modelling approach to further help explain the distribution of pups of various stages. Adult female grey seals show a preference for both pupping sites and subsequent habitat near to pools of water of low salinity at intermediate distances to access points to the sea, though appear to exhibit stronger preferences regarding the characteristics of their habitat than pupping site. It is concluded that these preferences are a result of a requirement for proximity to pools for thermoregulation and for drinking water to avoid a negative water balance. However, females do not typically choose sites directly next to or within pools, this is a result of a trade-off between proximity to pools and proximity to their pup, which is at greater risk when separated from its mother, or close to pools in areas of high adult density. It also appears likely that females choose sites at intermediate proximity to access points as sites directly next to access points experience greater disturbance from other seals arriving to, or leaving, the colony. The widespread availability of apparently suitable habitat suggests that the North Rona colony is not restricted in size by limited availability of suitable pupping sites; other potential drivers of the decline of the North Rona colony are therefore discussed, with recommendations for future research. A parallel analysis investigating pup habitat use showed that weaned pups, unlike neonates, appear to avoid locations near to adult female grey seals. It is concluded that this is a result of social interactions driving weaned pups into areas abandoned, or not yet colonised, by adult females, which are aggressive towards conspecifics during lactation. Overall, the ENFA has provided an excellent means to assess the terrestrial pupping site and subsequent habitat preferences of the grey seal, though alternative approaches are suggested for also assessing social influences on space use.
Download or read book Behaviour of the grey seal Halichoerus grypus Fab in the spring written by K.M. BACKHOUSE and published by . This book was released on 1957 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Behaviour of grey seals Halichoerus grypus during a breeding season at North Rona written by S.S. ANDERSON and published by . This book was released on 1975 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Assessing the Exposure and Behavioural Response of Grey Seals Halichoerus Grypus to Shipping Noise written by Leah Trigg and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Individual Differences in Maternal Behaviour in the Grey Seal Halichoerus Grypus and the Impact of Disturbance at Donna Nook written by Hani Myfanwy Castle James and published by . This book was released on 2013 with total page 142 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract:The grey seal (Halichoerus grypus) is a semi-aquatic pinniped and a member of the family phocidae. On shore breeding colonies form around the UK during the autumn, on which female grey seals rear a single pup for up to 3 weeks. This study aimed to identify the presence, if any, of consistent individual differences (CIDs) in maternal behaviour of grey seals on the breeding colony at Donna Nook. Data collection was non-intrusive, using in-field focal videos, pup-check counts and proximity maps. In agreement with previous research on North Rona, results from the current study show CIDs in pup-check behaviour at Donna Nook. CIDs were present in time mothers spent interacting with their pup and time spent nursing. These findings provide preliminary evidence for the existence of grey seal personalities, or more specifically, mothering styles. There was no evidence that pup gender influenced maternal behavioural investment. There was evidence for habituation to human disturbance; females exposed to the public showed a lower duration of alert behaviour and no difference in duration of pup interaction compared to the restricted site. This habituation was no longer evident following exposure to sudden disturbance (in this case, an unforeseen tidal storm surge). A colony wide increase in pup-check duration and decrease in colony density was observed in the weeks following the storm surge. The results of this study highlight the scope for future research into the stability of these CIDs over numerous breeding seasons and effects of these differences on pup development. Perhaps most importantly, this study provides the first photographic identification catalogue for females at Donna Nook, an excellent basis for future research.
Download or read book IN SITU MEASUREMENTS BY INSTRUMENTED GREY SEALS HALICHOERUS GRYPUS REVEAL FINE SCALE OCEANOGRAPHIC PROPERTIES AND ENVIRONMENTAL INFLUENCES ON MOVEMENT PATTERNS written by Bernadette Nowak and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The influence of oceanographic conditions on the movements of large marine predators has been demonstrated in diverse taxa. However, obtaining subsurface data that are spatio-temporally relevant to the decisions made by benthically-foraging species can be challenging. Between the years 2009 and 2015, 117 grey seals (Halichoerus grypus) were captured on Sable Island, NS and instrumented with Mk10-AF FastlocTM GPS devices. A bio-optical model for the estimation of chlorophyll-a using light attenuation was developed by performing a replicated experiment in the Bedford Basin. This model was applied to data collected in situ by grey seals and, along with other oceanographic conditions, mapped across the Scotian Shelf, providing high spatio-temporal coverage. Behavioural states were estimated from location data using the hidden Markov movement model. Generalized linear mixed-effects models indicated that grey seal behaviours are influenced by the fine-scale chlorophyll-a and environmental conditions they encounter across the oceanographically heterogeneous Scotian Shelf.
Download or read book Atmospheric and Oceanographic Effects on Grey Seal Halichoerus Grypus and Harbour Seal Phoca Vitulina Haul out Behaviour in Findhorn Bay written by Felicity Johnson and published by . This book was released on 2016 with total page 61 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Effects of Habitat on Population Dynamics in an Expanding Population of Grey Seals Halichoerus Grypus on Muskeget Island MA written by Meagan Sims and published by . This book was released on 2013 with total page 248 pages. Available in PDF, EPUB and Kindle. Book excerpt: Breeding grey seals (Halichoerus grypus) utilize a variety of terrestrial substrates for parturition, nursing, and mating that vary in topographical characteristics and therefore, the availability of suitable habitat is crucial for the persistence of grey seal populations worldwide. This study compared the effects of habitat type over the course of four breeding seasons on Muskeget Island, Massachusetts within and between years on a suite of population parameters including densities, sex ratios, male harem likelihood and mean harem sizes, pups with and without mothers, nursing events, copulation events, pup mortality, and pup developmental stages. The analysis included the 2007, 2008, 2010, and 2012 breeding seasons and compared two beach and three interior habitat types. I predicted that the predominant pupping habitat type used during the breeding season would be exterior beach types because they were composed of expansive, primarily flat substrate representing the first access points when hauling-out. It was expected that these sites would be the locations used by early arriving females and contain higher densities of all age/sex classes. Areas with higher densities were thought to facilitate a greater number of harems with smaller mean harem sizes, fewer pups with mothers, fewer nursing events, more copulation events, higher pup mortality, and more pups in later developmental stages. Overall, densities for all age/sex classes were significantly higher for exterior open beach and thin beach types compared to interior marsh, back beach grass, and inland types, and the use of interior habitats was higher overall in 2012 than in 2007. Sex ratios became more female biased over the course of the study, and were more heavily femaled biased in interior habitat types. Males were more likely to have harems in open beach types while mean harem sizes were significantly larger in interior habitat types, higher in 2012 than 2007, and significantly positively correlated with adult sex ratios in three out of five habitat types. Densely populated exterior sites had more observed copulation events and pup mortality while no differences in nursing events were found. Additionally, a clear shift in habitat use was evident for the 2010 breeding season for all population parameters. Results suggest the primary use of exterior beach habitats during the initial portion of the breeding season, particularly on the north and west sides of Muskeget, with a progression towards interior habitats throughout the season and the use of interior habitat becoming more prevalent over time. As expected, distinct differences in all population parameters were observed for beach vs. interior habitat use, suggesting habitat type plays a considerable role in the population dynamics of breeding grey seals. To date, little is known regarding this breeding population and this study was the first analysis conducted on Muskeget Island to investigate grey seal pupping habitat choice and its potential effects on population dynamics.
Download or read book Feeding Ecology of the Northwest Atlantic Grey Seal Halichoerus Grypus microform written by Donald Benoit and published by National Library of Canada. This book was released on 1989 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Human Impacts on Seals Sea Lions and Sea Otters written by Todd J. Braje and published by Univ of California Press. This book was released on 2011-03-23 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt: “The bones recovered from the middens of the northeastern Pacific shorelines have important stories to tell biologists, marine mammalogists, and those concerned with marine conservation. This volume unearths a wealth of information about the historical ecology of seals, sea lions, and sea otters in the North Pacific that spans thousands of years. It provides fascinating insights into how the world once looked, and how it may one day look again as seals, sea lions, and sea otters reclaim and recolonize their former haunts.”—Andrew Trites, Director, Marine Mammal Research Unit, University of British Columbia “Braje and Rick have assembled a compelling set of case studies on the long-term and complex interactions between people, marine mammals, and environments in the Northeast Pacific. The promise of zooarchaeology as historical science is on full display, as researchers use geochemistry, aDNA, morphometrics, and traditional analytic methods to address questions of utmost importance to the long-term health of coastal ecosystems. If this book doesn't convince conservation biology about the need to take the long view of animal histories and ecosystems into account in developing conservation management plans, I'm not sure what will.”—Virginia L. Butler, Department of Anthropology, Portland State University
Download or read book Treatment of Contaminated Dredged Material written by and published by . This book was released on 1978 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Birds and Climate Change written by and published by Elsevier. This book was released on 2004-11-13 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Temperature and other climate variables are currently changing at a dramatic rate. As observations have shown, these climatic changes have serious consequences for all organisms and their ability to adapt to changing environmental conditions. Birds are excellent model organisms, with a very active metabolism, they are highly sensitive to environmental changes and as highly mobile creatures they are also extremely reactive. Birds and Climate Change discusses our current knowledge of observed changes and provides guidelines for studies in the years to come so we can document and understand how patterns of changing weather conditions may affect birds. - Provides reviews of long-term datasets - Incorporates meta-analyses of studies about climate change effects on birds - Includes guidelines and suggestions for further studies
Download or read book Seal Cull written by John Lister-Kaye and published by Penguin Group. This book was released on 1979 with total page 192 pages. Available in PDF, EPUB and Kindle. Book excerpt:
