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Timeline of Jennifer Schmidt

2017
Apr
04
Published new article




Article

Transitions of social-ecological subsistence systems in the Arctic

Published: 04 April 2017 by Uopen Journals in International Journal of the Commons

doi: 10.18352/ijc.698

3 Reads | 4 Citations
2015
Aug
20
Published new article




Article

Demographic and economic disparities among Arctic regions

Published: 20 August 2015 by Informa UK Limited in Polar Geography

doi: 10.1080/1088937x.2015.1065926

We use demographic and economic indicators to analyze spatial differences and temporal trends across 18 regions surrounding the Arctic Ocean. Multifactor and cluster analysis were used on 10 indicators reflecting income, employment and demography from 1995 to 2008. The main difference is between regions with high population densities, low natural growth rate, and low unemployment (Russia, Norway and Iceland) and regions with high unemployment rate and high natural growth rate (mainly North American regions). However, once those parameters were accounted for sub-regional differences start to emerge. Variation among the regions was a result of national policies and regional differences such as access and presence of natural resources (i.e. oil, gas, mining, etc.). We found only weak temporal trends, but regions with resource extraction show some signs of higher volatility. Overall, the Arctic has experienced out-migration with only Iceland and two regions in Canada experiencing in-migration.

0 Reads | 2 Citations
2015
Jul
14
Published new article




Article

Detecting, estimating, and correcting for biases in harvest data

Published: 14 July 2015 by Wiley in The Journal of Wildlife Management

doi: 10.1002/jwmg.928

Hunting is important to many people because it provides food, recreation, and cultural identity, so proper management of wildlife is necessary. Wildlife agencies and researchers often rely on harvest data supplied by hunters, but interpretation of these data can be misleading when biases are not acknowledged, assessed, and corrected. We use harvest information collected by the Alaska Department of Fish and Game (ADF&G) from moose (Alces alces gigas) hunters to examine and correct 3 common biases in harvest data: heaping in responses of estimated effort (i.e., rounding), changes in report design, and nonreporting. We found that bias due to heaping was limited (2.8%). A large increase in special permits in 2004 (6.1% in 2003 and 40.1% in 2004) corresponded with increases in individuals with multiple permits (8.6% and 17.3%), which biased estimates of hunt participation calculated from permit data. Failure to correct for multiple reports per hunter also resulted in an artificial decline in success over time. Road access influenced reporting rates; rural Alaska residents without a road had the lowest reporting rate (67%) and rural with a road the greatest (82%). A statewide trend of 663 additional hunters per year calculated from raw permit data was eliminated once data were corrected for both multiple permits and nonreporting. Late reporters were also less likely to hunt (11.8%) than all reporters. Our research shows that survey data bias can significantly influence data interpretation, and wildlife managers must balance information needs, time constraints, and financial resources when determining which biases to correct. © 2015 The Wildlife Society.

0 Reads | 5 Citations
2014
Jul
04
Published new article




Article

Relationship of Community Characteristics to Harvest Reporting: Comparative Study of Household Surveys and Harvest Ticke...

Published: 04 July 2014 by Informa UK Limited in Human Dimensions of Wildlife

doi: 10.1080/10871209.2014.917219

0 Reads | 4 Citations
2012
Oct
01
Published new article




Article

Plant toxins and trophic cascades alter fire regime and succession on a boreal forest landscape

Published: 01 October 2012 by Elsevier BV in Ecological Modelling

doi: 10.1016/j.ecolmodel.2012.06.022

Two models were integrated in order to study the effect of plant toxicity and a trophic cascade on forest succession and fire patterns across a boreal landscape in central Alaska. One of the models, ALFRESCO, is a cellular automata model that stochastically simulates transitions from spruce dominated 1 km2 spatial cells to deciduous woody vegetation based on stochastic fires, and from deciduous woody vegetation to spruce based on age of the cell with some stochastic variation. The other model, the ‘toxin-dependent functional response’ model (TDFRM) simulates woody vegetation types with different levels of toxicity, an herbivore browser (moose) that can forage selectively on these types, and a carnivore (wolf) that preys on the herbivore. Here we replace the simple succession rules in each ALFRESCO cell by plant–herbivore–carnivore dynamics from TDFRM. The central hypothesis tested in the integrated model is that the herbivore, by feeding selectively on low-toxicity deciduous woody vegetation, speeds succession towards high-toxicity evergreens, like spruce. Wolves, by keeping moose populations down, can help slow the succession. Our results confirmed this hypothesis for the model calibrated to the Tanana floodplain of Alaska. We used the model to estimate the effects of different levels of wolf control. Simulations indicated that management reductions in wolf densities could reduce the mean time to transition from deciduous to spruce by more than 15 years, thereby increasing landscape flammability. The integrated model can be useful in estimating ecosystem impacts of wolf control and moose harvesting in central Alaska.

0 Reads | 3 Citations
2010
Jul
01
Published new article




Article

Resilience of Athabascan subsistence systems to interior Alaska’s changing climateThis article is one of a selection of ...

Published: 01 July 2010 by Canadian Science Publishing in Canadian Journal of Forest Research

doi: 10.1139/X10-108

Subsistence harvesting and wild food production by Athabascan peoples is part of an integrated social–ecological system of interior Alaska. We describe effects of recent trends and future climate change projections on the boreal ecosystem of interior Alaska and relate changes in ecosystem services to Athabascan subsistence. We focus primarily on moose, a keystone terrestrial subsistence resource of villages in that region. Although recent climate change has affected the boreal forest, moose, and Athabascan moose harvesting, a high dependence by village households on moose persists. An historical account of 20th century socioeconomic changes demonstrates that the vulnerability of Athabascan subsistence systems to climatic change has in some respects increased while at the same time has improved aspects of village resilience. In the face of future climate and socioeconomic changes, communities have limited but potentially effective mitigation and adaptation opportunities. The extent to which residents can realize those opportunities depends on the responsiveness of formal and informal institutions to local needs. For example, increases in Alaska’s urban population coupled with climate-induced habitat shifts may increase hunting conflicts in low-moose years. This problem could be mitigated through adaptive co-management strategies that project future moose densities and redirect urban hunters to areas of lower conflict.

0 Reads | 27 Citations
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