Perspectives On The Dynamic Human-Walrus Relationship

Thesis (Ph.D.) University of Alaska Fairbanks, 2008Changes in sea ice conditions have direct bearing on ice-associated species such as Pacific walrus (Odobenus rosmarus divergens), which are an important component of subsistence for Alaska Native communities in the Bering Sea. I explore the relationship between walrus, sea ice, and Alaska Native subsistence at Diomede, Gambell, and Savoonga between 1952 and 2004 to better understand walrus ecology and subsistence under different climatic regimes. I then consider how the inability to reliably and regularly count walrus and other ice-associated pinnipeds in this dynamic environment challenges effective management of walrus and subsistence under the Marine Mammal Protection Act (MMPA). However, the primary management goals of the MMPA, which are intended to be ecosystem-based, have been bypassed in favor of a numerical population assessment approach. Governance approaches such as adaptive co-management, using a suite of ecological and population indicators have theoretical promise for making management responsive to both observed ecosystem and population changes. Nevertheless, understanding outcomes of co-management has proven difficult. To address this, I argue that such an understanding requires not only a review of a statute's ecosystem-oriented goals, but also a critical consideration of the specific goals of each co-management partner. To sustain natural resources, mismatches between the scale of ecological processes regulating resources, and the social or political processes governing resource use should logically be reduced, thus improving what is termed "fit." I argue that failures to foster fit of these processes might better reflect underlying co-management partner goals, rather than a focus on the statutory goals of policy. I examine this claim by assessing the spatial and temporal "fit" of boundaries defining the political context of walrus co-management under the MMPA. I find that the ability to address the uncertainty of walrus population status in a manner benefiting adaptation of both walrus and Alaska Natives to a dynamic environment is compromised by a focus on values, rather than better matching policy with ecological and social conditions. My interdisciplinary findings are broadly applicable to community-based conservation partners seeking to foster resilience and adaptation of both natural resources and of the indigenous or rural communities dependent on them

Changes in proximate composition and somatic energy content for Pacific sand lance (Ammodytes hexapterus) from Kachemak Bay, Alaska relative to maturity and season.

Abstract kJg to a maximum of 19.68 kJg , and (per g) are higher than adults in late summer. The seasonal food value of adult sand lance to predators varies markedly, but maximum energetic value coincides with important feeding periods for marine mammals, fish, and seabirds. Published by Elsevier Science B. V

Terrain Features and Architecture of Wolverine (Gulo gulo) Resting Burrows and Reproductive Dens on Arctic Tundra

Burrowing species rely on subterranean and subnivean sites to fulfill important life-history and behavioral processes, including predator avoidance, thermoregulation, resting, and reproduction. For these species, burrow architecture can affect the quality and success of such processes, since characteristics like tunnel width and chamber depth influence access by predators, thermal insulation, and energy spent digging. Wolverines (Gulo gulo) living in Arctic tundra environments dig burrows in snow during winter for resting sites and reproductive dens, but there are few published descriptions of such burrows. We visited 114 resting burrows and describe associated architectural characteristics and non-snow structure. Additionally, we describe characteristics of 15 reproductive den sites that we visited during winter and summer. Although many resting burrows were solely excavated in snow, most incorporated terrain structures including cliffs, talus, river shelf ice, thermokarst caves, and stream cutbanks. Burrows typically consisted of a single tunnel leading to a single chamber, though some burrows had multiple entrances, branching tunnels, or both. Tunnels in resting burrows were shorter than those in reproductive dens, and resting chambers were typically located at the deepest part of the burrow. Reproductive dens were associated with snowdrift-forming terrain features such as streambeds, cutbanks on lake edges, thermokarst caves, and boulders. Understanding such characteristics of Arctic wolverine resting and reproductive structures is critical for assessing anthropogenic impacts as snowpack undergoes climate-driven shifts.Les espèces fouisseuses dépendent de lieux enfouis sous la terre et sous la neige pour satisfaire leurs importants processus de vie et de comportement, y compris l’évitement des prédateurs, la thermorégulation, le repos et la reproduction. Pour ces espèces, l’architecture des terriers peut avoir des effets sur la qualité et la réussite des processus, car des caractéristiques comme la largeur des tunnels et la profondeur des chambres influencent l’accès aux terriers par les prédateurs, l’isolation thermique et l’énergie dépensée pour creuser. L’hiver, les carcajous (Gulo gulo) qui vivent dans les environnements de la toundra de l’Arctique creusent des terriers dans la neige afin de s’en servir comme aires de repos et comme tanières de reproduction. Cependant, peu de descriptions de tels terriers ont été publiées. Nous avons visité 114 terriers de repos, puis nous avons décrit leurs caractéristiques architecturales et les structures connexes n’étant pas recouvertes de neige. Par ailleurs, nous décrivons les caractéristiques de 15 tanières de reproduction que nous avons visitées en hiver et en été. Même si de nombreux terriers de repos ont été uniquement creusés dans la neige, la plupart des terriers incorporaient des structures topographiques, dont des falaises, des talus, de la glace de banquise, des grottes thermokarstiques et des hautes berges de cours d’eau. En général, les terriers étaient composés d’un seul tunnel menant à une seule chambre, bien que certains avaient plusieurs entrées, des galeries, ou les deux. Les tunnels des aires de repos étaient moins longs que ceux des tanières de reproduction, et les chambres de repos étaient généralement situées dans la partie la plus profonde des terriers. Les tanières de reproduction étaient installées dans des caractéristiques topographiques où s’amoncelle la neige, comme les lits de cours d’eau, les hautes berges de lacs, les grottes thermokarstiques et les rochers. Il est essentiel de comprendre les caractéristiques des structures de repos et de reproduction des carcajous de l’Arctique afin d’être en mesure d’évaluer les incidences anthropiques au moment où le manteau neigeux subit des changements liés au climat

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Biomass offsets little or none of permafrost carbon release from soils, streams, and wildfire : an expert assessment

As the permafrost region warms, its large organic carbon pool will be increasingly vulnerable to decomposition, combustion, and hydrologic export. Models predict that some portion of this release will be offset by increased production of Arctic and boreal biomass; however, the lack of robust estimates of net carbon balance increases the risk of further overshooting international emissions targets. Precise empirical or model-based assessments of the critical factors driving carbon balance are unlikely in the near future, so to address this gap, we present estimates from 98 permafrost-region experts of the response of biomass, wildfire, and hydrologic carbon flux to climate change. Results suggest that contrary to model projections, total permafrost-region biomass could decrease due to water stress and disturbance, factors that are not adequately incorporated in current models. Assessments indicate that end-of-the-century organic carbon release from Arctic rivers and collapsing coastlines could increase by 75% while carbon loss via burning could increase four-fold. Experts identified water balance, shifts in vegetation community, and permafrost degradation as the key sources of uncertainty in predicting future system response. In combination with previous findings, results suggest the permafrost region will become a carbon source to the atmosphere by 2100 regardless of warming scenario but that 65%-85% of permafrost carbon release can still be avoided if human emissions are actively reduced.Peer reviewe

Ecology and demographics of Pacific sand lance, Ammodytes hexapterus Pallas, in Lower Cook Inlet, Alaska

Distinct sand lance populations occur within the relatively small geographic area of Lower Cook Inlet, Alaska. Marked meso-scale differences in abundance, growth, and mortality existed as a consequence of differing oceanographic regimes. Growth rate within populations (between years) was positively correlated with temperature. -- However, this did not extend to inter-population comparisons where differing growth rates were better correlated to marine productivity. Opaque otoliths form in juvenile sand lance during their first summer coinciding with their period of rapid growth. Subsequent opaque zones are deposited during spring, in conjunction with rapidly increasing water temperatures. Areal rather than radial descriptors of otolith size provide the best relation to sand lance length. A single linear regression was insufficient to describe this relationship with separate linear regressions needed for both juveniles and adults. No sexual dimorphism was observed for sand lance in length-at-weight (gonad-free) or length-at-age. Most sand lance reached maturity in their second year. Field observations and indices of maturity, gonad development, and ova-size distribution all indicated that sand lance spawn once each year. Males mature earlier in the season than females, but females (31 %) attain a higher gonadosomatic index than males (21 %). Sand lance spawned intertidally in late September and October on fine gravel/sandy beaches soon after the seasonal peak in water temperatures. Fecundity of females (93-199 mm) was proportional to length, ranging from 1,468 to 16,081 ova. Spawned eggs were 1.02 ± 0.08 mm in diameter, demersal, slightly adhesive, and deposited in the intertidal just below the waterline. Sand lance embryos developed over 67 days through periods of intertidal exposure and sub-freezing air temperatures. Mean dry-weight energy value of sand lance cycles seasonally, peaking in spring and early summer (20.91 klg-1 for males, 21.08 kJg-1 for females), and subsequently declining by about 25 % during late summer and fall (15.91 kJg-1 for males, 15.74 kJg-1 for females). Declines in energy density during late summer paralleled gonadal development, sand lance entering the winter with close to their minimum whole body energy content. Dry weight energy densities of juveniles increased from a minimum 16.67 kJg-1 to a maximum of 19.68 kJg-1 and are higher than adults in late summer

Relevance of a Particularly Sensitive Sea Area to the Bering Strait Region: a Policy Analysis Using Resilience-Based Governance Principles

The Bering Strait, separating the North American and Asian continents, is a productive social-ecological marine system that is vulnerable to increasing maritime traffic. In other parts of the world, the International Maritime Organization (IMO), an agency of the United Nations, has designated similar marine systems as a Particularly Sensitive Sea Area (PSSA) in an effort to protect vulnerable resources from international shipping. We present information about the 14 existing PSSAs around the world and the political process by which designation is achieved. We examine specific characteristics of the Bering Strait system that are relevant to a PSSA application; these include vulnerable resources such as marine mammals and their contribution to the food and cultural security of indigenous communities, threats to these resources from shipping activities, and the viable mitigation options to reduce these threats. We then use five criteria derived from empirical research on resilience-based governance to analyze whether a PSSA designation would promote the resilience of marine mammal populations and indigenous communities to increased maritime activities. Despite the elusiveness of a definitive answer, we conclude that although the designation is not a perfect fit from a theoretical standpoint, it still holds the potential to benefit marine mammals and indigenous communities in terms of resilience. We conclude by identifying critical challenges and trade-offs that practitioners would need to negotiate when attempting to apply theoretical governance principles via real-world policy tools

Spring food habits of Wolverine (Gulo gulo) in the Colville River watershed, Alaska

Wolverines (Gulo gulo) are relatively abundant on the North Slope of Alaska, an Arctic ecosystem dominated by tundra habitats that run north from the Brooks Range across a wide coastal plain to the Beaufort Sea. The region contains a range of potential Wolverine prey species, including ungulates (Caribou [Rangifer tarandus], Moose [Alces americanus]), Arctic Ground Squirrel (Urocitellus parryii), and both Soricidae and Cricetidae species. The seasonal composition of these, and other prey species, in the Wolverines’ diet is not well understood. We collected Wolverine scats during spring (March–May) on the North Slope while tracking animals from snowmobiles and with helicopters that visited areas identified as of interest during ground surveys or using global positioning system collared animals. We analyzed prey remains in 48 scat samples based on hair, bone, and other prey fragments. We then calculated frequency of occurrence, percentage of occurrence, and weighted percent volume for each major prey category detected. We confirmed species identity of scats as Wolverine by amplifying the control region of the mitochondrial DNA. We estimated spring diet diversity and richness based on nine major prey categories detected in scats. Ungulates and cricetids together constituted 69% of the Wolverines’ spring diet, with Snowshoe Hare (Lepus americanus) constituting 9%, fox (Vulpes spp.) 6%, Arctic Ground Squirrel 2%, birds 2%, American Beaver (Castor canadensis) less than 1%, and unknown 6%

Predation on Caribou (Rangifer tarandus) by Wolverines (Gulo gulo) after long pursuits

Ungulates are an important source of food for Wolverines (Gulo gulo), especially in winter when scavenging on carcasses is a primary means of obtaining food. However, Wolverines are also known to prey on ungulates. We followed fresh tracks of Wolverines pursuing Caribou (Rangifer tarandus) on six occasions on the tundra of northern Alaska in 2011, 2015, 2017, and 2018; all ended in a predation event after pursuits of 4−62 km. Exhaustion of the Caribou after long pursuits appeared to contribute to the success of predation attempts. Snow conditions appeared to be a factor in only one of the six cases