{"id":303,"date":"2015-10-29T19:08:12","date_gmt":"2015-10-29T19:08:12","guid":{"rendered":"https:\/\/grad.biology.ualberta.ca\/derocher\/?page_id=303"},"modified":"2015-10-29T19:11:05","modified_gmt":"2015-10-29T19:11:05","slug":"stephen-hamilton","status":"publish","type":"page","link":"https:\/\/grad.biology.ualberta.ca\/derocher\/stephen-hamilton\/","title":{"rendered":"Stephen Hamilton"},"content":{"rendered":"\n\n
\n
\n \"http:\/\/www.biology.ualberta.ca\/faculty\/bio-1136\/uploads\/images\/sghamilt01.png\" <\/div>\n<\/td>\n<\/tr>\n<\/table>\n

Stephen Hamilton<\/strong><\/p>\n

e-mail:stephen.hamilton@ualberta.ca<\/a><\/p>\n

PhD Student<\/strong><\/p>\n

University of Alberta<\/strong><\/p>\n

"Polar Bear Conservation in the Circumpolar
\nArctic: Population, Habitat, and Climate Projections"<\/strong><\/p>\n

The scale at which habitat change occurs has significant
\nimplications on the species populations.  With the earth in a period of climate warming, changes are being
\ndetected globally and therefore all species are likely to be affected in some
\nform1<\/sup>.  While ecosystem
\nchange is normal, the concern about present-day global warming is that it is
\nhappening too rapidly for many species to cope via generational
\nadaptation.  Approximately half the
\nworld’s land and marine mammals are in a state of decline, and one in four
\nspecies is threatened with extinction due primarily to habitat loss2<\/sup>.  In the Arctic, climate change is
\nresponsible for shrinking the average Arctic sea-ice cover, thus affecting a
\nwide variety of Arctic marine species3<\/sup>.<\/p>\n

\"\"\"\"<\/p>\n



\n
Polar bears (Ursus maritimus<\/em>) are among those marine mammals affected by climate
\nchange4,5<\/sup> as Arctic Ocean temperatures increase6<\/sup> and
\nsea-ice cover decreases7<\/sup>.  Polar bears require sea-ice cover as a hunting platform, and some
\npopulations, such as those in the Beaufort Sea, rely on multi-year ice for
\ndenning, making this species particularly sensitive to Arctic climate change4<\/sup>.  Habitat loss due to climate change is
\npredicted to result in an overall reduction in the global polar bear population8<\/sup>.<\/p>\n

My research focuses on polar bear habitat
\nchange due to climate warming, and the resulting effects on the population in
\nthe following ways:<\/p>\n

1)   Understanding the link between
\nArctic environmental conditions and population.<\/span><\/p>\n

2)   Examining the effects on
\npopulation, spatially and numerically, based on sea-ice projection models.<\/span><\/p>\n

3)   Studying the movement patterns
\nof bears by demographic group relative to changing sea-ice conditions, and
\nassessing the projected vulnerability due to modeled changes in habitat.<\/span><\/p>\n

4)   Assessing the vulnerability of
\npolar bears by demographic group to hunting, and the conservation implications
\ntherein.<\/span><\/p>\n

RECENT PUBLICATION<\/p>\n

Projected Polar Bear Sea Ice
\nHabitat in the Canadian Arctic Archipelago<\/strong><\/p>\n

Available
\nOnline at PLOS ONE<\/a><\/p>\n

Abstract:<\/strong><\/p>\n

Background<\/u>: Sea ice across the
\nArctic is declining and altering physical characteristics of marine ecosystems.
\nPolar bears (Ursus maritimus<\/em>) have
\nbeen identified as vulnerable to changes in sea ice conditions. We use sea ice
\nprojections for the Canadian Arctic Archipelago from 2006 \u2013 2100 to gain
\ninsight into the conservation challenges for polar bears with respect to
\nhabitat loss using metrics developed from polar bear energetics modeling.<\/p>\n

Principal
\nFindings<\/u>:
\nShifts away from multiyear ice to annual ice cover throughout the region, as
\nwell as lengthening ice-free periods, may become critical for polar bears
\nbefore the end of the 21st century with projected warming. Each polar bear population
\nin the Archipelago may undergo 2\u20135 months of ice-free conditions, where
\nno such conditions exist presently. We identify spatially and temporally explicit
\nice-free periods that extend beyond what polar bears require for nutritional and
\nreproductive demands.<\/p>\n

Conclusions\/Significance<\/u>: Under
\nbusiness-as-usual climate projections, polar bears may face starvation and
\nreproductive failure across the entire Archipelago by the year 2100.<\/p>\n

Citation<\/em>: Hamilton SG, Castro
\nde la Guardia L, Derocher AE, Sahanatien V, Tremblay B, et al. (2014) Projected
\nPolar Bear Sea Ice Habitat in the Canadian Arctic Archipelago. PLoS ONE 9(11):
\ne113746. doi:10.1371\/journal.pone.0113746<\/p>\n

REFERENCES:<\/p>\n

(1) Walther et al. 2002, Nature<\/em>; (2) Schipper et al. 2008, Science<\/em>; (3) Laidre et al. 2008, Ecological Applications<\/em>; (4) Derocher et
\nal. 2004, Integrative and Comparative
\nBiology<\/em>; (5) Hunter et al. 2010, Ecology<\/em>;
\n(6) Zhang 2005, Geophysical Research
\nLetters<\/em>; (7) Serreze et al. 2007, Science<\/em>;
\n(8) Durner et al. 2009, Ecological
\nMonographs<\/em>.<\/p>\n","protected":false},"excerpt":{"rendered":"

Stephen Hamilton e-mail:stephen.hamilton@ualberta.ca PhD Student University of Alberta "Polar Bear Conservation in the Circumpolar Arctic: Population, Habitat, and Climate Projections" The scale at which habitat change occurs has significant implications on the species populations.  With the earth in a period of climate warming, changes are being detected globally and therefore all species are likely to […]<\/p>\n","protected":false},"author":60,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-303","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/pages\/303","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/users\/60"}],"replies":[{"embeddable":true,"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/comments?post=303"}],"version-history":[{"count":3,"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/pages\/303\/revisions"}],"predecessor-version":[{"id":307,"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/pages\/303\/revisions\/307"}],"wp:attachment":[{"href":"https:\/\/grad.biology.ualberta.ca\/derocher\/wp-json\/wp\/v2\/media?parent=303"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}