scholarly journals Use of Multiple Methods to Estimate Walrus (Odobenus rosmarus rosmarus) Abundance in the Penny Strait-Lancaster Sound and West Jones Sound Stocks, Canada

2014 ◽  
Vol 9 ◽  
pp. 95 ◽  
Author(s):  
Robert EA Stewart ◽  
Erik W Born ◽  
J Blair Dunn ◽  
William R Koski ◽  
Anna K Ryan

Surveys to estimate walrus abundance at terrestrial haulout sites in the Penny Strait-Lancaster Sound (PS-LS) and West Jones Sound (WJS) stocks were conducted in 1977 and 1998-2009. The Minimum Counted Population (MCP) was similar in 1977 (565) to recent years (557) for the PS-LS stock. The MCP for the WJS stock was higher in recent surveys (404) than in 1977 (290). Regression analysis of MCP and density (number of walrus divided by number of haulouts surveyed) showed no significant trends over time. We also calculated bounded count estimates for comparison. Finally, we used broad-scale behavioural data to estimate the proportion of the total stock that could be considered countable, to produce two adjusted estimates. We selected recent surveys with good coverage and ignored adjusted estimates that were lower than MCP. For the PS-LS stock, the adjusted MCP (with 95% CL) was 672 (575-768) and 727 (623-831) walrus in 2007 and 2009, respectively. For WJS, the best estimates were the adjusted MCP of 503 (473-534) in 2008 and the adjusted bounded count of 470 (297-1732) in 2009. While both stocks appear to have remained stable over three decades, differences in survey coverage and possible differences in walrus distribution make precise population estimation difficult.

2014 ◽  
Vol 9 ◽  
pp. 219 ◽  
Author(s):  
D Bruce Stewart ◽  
Jeff W Higdon ◽  
Randall R Reeves ◽  
Robert EA Stewart

Knowledge of changes in abundance of Atlantic walruses (Odobenus rosmarus rosmarus) in Canada is important for assessing their current population status. This catch history collates available data and assesses their value for modelling historical populations to inform population recovery and management. Pre-historical (archaeological), historical (e.g., Hudson Bay Company journals) and modern catch records are reviewed over time by data source (whaler, land-based commercial, subsistence etc.) and biological population or management stock.Direct counts of walruses landed as well as estimates based on hunt products (e.g., hides, ivory) or descriptors (e.g., Peterhead boatloads) support a minimum landed catch of over 41,300 walruses in the eastern Canadian Arctic between 1820 and 2010. Little is known of Inuit catches prior to 1928, despite the importance of walruses to many Inuit groups for subsistence. Commercial hunting from the late 1500s to late 1700s extirpated the Atlantic walrus from Quebec and the Atlantic Provinces, but there was no commercial hunt for the species in the Canadian Arctic until ca. 1885. As the availability of bowhead whale (Balaena mysticetus) declined, whalers increasingly turned to hunting other species, including walruses. Modest numbers (max. 278/yr) were taken from the High Arctic population in the mid-1880s and large catches (up to 1400/yr) were often taken from the Central Arctic population from 1899 -1911, while the Foxe Basin stock (Central Arctic population) and Low Arctic population were largely ignored by commercial hunters. Land-based traders (ca. 1895-1928) continued the commercial hunt until regulatory changes in 1928 reserved walruses for Inuit use. Since 1950, reported walrus catches have been declining despite a steady increase in the Inuit population. Effort data are needed to assess whether lower catches stem from declining hunter effort or decreased walrus abundance. The recent take of walruses by sport hunting has been small (n=141, 1995-2010), sporadic and local.These landed catch estimates indicate the minimum numbers of walruses removed but do not account for under-reporting or lost animals that were killed but were not secured. Unreported and lost animals may represent a significant fraction of the total removals and must be considered in any modelling exercise. The sources, quality and completeness of the catch data vary widely over time and space and between the different hunt types. This variability confounds interpretation and contributes to the uncertainty that needs to be incorporated into any modelling. The data on Inuit subsistence catches before ca. 1928 are particularly fragmentary and uncertain. 


Author(s):  
Manuel Fröhlich ◽  
Abiodun Williams

The Conclusion returns to the guiding questions introduced in the Introduction, looking at the way in which the book’s chapters answered them. As such, it identifies recurring themes, experiences, structures, motives, and trends over time. By summarizing the result of the chapters’ research into the interaction between the Secretaries-General and the Security Council, some lessons are identified on the changing calculus of appointments, the conditions and relevance of the international context, the impact of different personalities in that interaction, the changes in agenda and composition of the Council as well as different formats of interaction and different challenges to be met in the realm of peace and security, administration, and reform, as well as concepts and norms. Taken together, they also illustrate the potential and limitations of UN executive action.


2021 ◽  
Vol 13 (13) ◽  
pp. 7191
Author(s):  
Valerie Paelman ◽  
Philippe Van Cauwenberge ◽  
Heidi Vander Bauwhede

We empirically test whether B Corp certification affects the short- and medium-term growth rates of sustainable enterprises. These businesses are growing in popularity and prevalence but, due to their hybrid nature, often suffer from external credibility issues and competing internal logics. Because of the rigorous and time-involving audit procedure, B Corp certification potentially sends a credible signal about the sustainable nature of the enterprise to its stakeholders. In addition, the B Corp label could help to straighten out internal tensions and align the company towards its dual purpose. Hence, B Corp certification could contribute to company success. We observe 129 firms that were certified between 2013 and 2018 over a period between six years prior and five years post-certification. Using propensity score matching, we identify 129 non-certified matching companies. On this sample, we conduct a difference-in-differences panel regression analysis to investigate the effect of certification. Our dataset allows us to study how the effects of B Corp certification evolve over time, which was previously untested. Our study documents a positive effect of B Corp certification on turnover growth and also that this effect increases with the time since certification, implying that certification requires some time for its full effect to become apparent.


1992 ◽  
Vol 8 (4) ◽  
pp. 418-420 ◽  
Author(s):  
Christian Lydersen ◽  
David Griffiths ◽  
Ian Gjertz ◽  
Oystein Wiig

2001 ◽  
Vol 34 (2) ◽  
pp. 299-319 ◽  
Author(s):  
Donley T. Studlar

Canada is unusual among advanced industrial democracies in having some provinces which regularly have greater voter turnouts for provincial than for federal elections. Provincial and federal turnouts by province in Canada are analyzed for the 1945-1998 period using multiple regression analysis, both for each set of elections and by comparing differences between the two. Federal turnout has declined over the years but provincial turnout appears to have increased slightly. Although the effects found here largely confirm previous findings about the relative effects of different types of variables found for the Canadian federal level only, several of the political explanations previously supported in cross-national research find less support. Instead, region, population density, months since the last federal or provincial election, and season of the year generally have greater and sometimes more consistent effects. This suggests the need for more studies of turnout in democracies at sub-central levels.


2015 ◽  
Vol 138 (3) ◽  
pp. 536-541 ◽  
Author(s):  
Jamie Kroft ◽  
Qing Li ◽  
Refik Saskin ◽  
Laurie Elit ◽  
Marcus Q. Bernardini ◽  
...  

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