Abstract

The Arctic system is dynamic and "change" is a part of its annual cycle. This annual cyclical change is characterized by extreme atmospheric temperatures; widely ranging sea ice extent; daylight from 0 to 24 hours per day; invasions and mass escapes of biota (migrations); and extreme morphologic, physiologic and behavioral adaptations of vertebrates for year round residents.^1-4 Thus, the biological components of this system are well adapted to the elegant synchrony of annual "feast and famine" and, in some ways, thrive on these extremes by providing a significant barrier to potential "invasives" (agents of disease, other vertebrate hosts, vectors of disease, industrialized and urbanized human habitation and exploitation, etc.) that affect health and disease conditions in the Arctic.^2-4 Decadal observations and predictions over the next century¹ are indicating that these conditions described above (frigid temperatures, extensive sea ice, etc.) are rapidly becoming less severe due to carbon-based gases and the positive feedback mechanism of increased temperatures releasing additional carbon-based "greenhouse" chemicals (plus feedback increasing temperatures). These changes may be "irreversible" on a millennial scale.⁵ Indeed, the biological invasion has begun and warming is well underway! What were once daunting enterprises in the Arctic are now logistically and economically feasible (two major shipping passages, offshore oil and gas, commercial fishing) because of technological advances and the reduced harshness of certain conditions. It is common to focus on the "losers" resulting from these changes, but the "winners" that will consequently fill these niches merit attention, as well since they will alter the disease and health status of current arctic species. This balance of "winners" and "losers" - and the broader consequences thereof - are hard to predict and understand. Agents of disease and vertebrate health status will be affected by, and play a role in, these dynamics as the environment changes and interacts in the "epidemiologic triad" (host-agent-environment) or "ecosystem health" paradigms. Unlike the Antarctic, the circumpolar Arctic has a long history of human habitation, so the human dimension is not new - just changing. This presentation will review the temperature driven changes and how 1) environmental cues are likely to become "uncoupled" (such as monthly mean temperatures and photoperiod), 2) loss of sea ice (extent, thickness) will alter human opportunities (shipping, oil and gas), 3) contaminants concentrations (e.g., mercury) may change over time and space, and 4) changes that are occurring will impact arctic marine vertebrates via the ecosystem health or epidemiologic triad perspectives (host-agent-environment interactions). It is not "change" that is causing the uncertainty, but the rate of change. The rate of change combined with potentially unprecedented extremes not achieved in recorded human history and poorly understood in the geological records (e.g., ice free Arctic Ocean in the summer) are driving much debate. Whether the various Arctic systems will be resilient, or not, and how they adapt to the changing environment and human technological advances is providing us numerous animal health and disease challenges that will be reviewed in this presentation via select examples.

Acknowledgements

I thank the numerous co-authors on papers related to this topic and the many colleagues and students that have participated in formal and informal discussions. I appreciate the opportunity to share some high latitude perspectives with the IAAAM.

Literature Cited

1.  AMAP. 2009. AMAP Update on Selected Climate Change Issues of Concern. Arctic Monitoring Assessment Program. Oslo v + 15pp.

2.  Bradley, M., S. Kutz, E. Jenkin, T. O'Hara. 2005. The Potential Impact of Climate Change on Infectious Diseases of Arctic Fauna. Int J Circumpolar Health 2005; 64(5): 468–478.

3.  Burek, K.A., F.M.D. Gulland, T.M. O'Hara. 2008. "Effects of Climate Change on Arctic Marine Mammal Health" In Assessing the Impacts of Climate Change on Arctic Marine Mammals, Special Issue Marine Mammal Commission (U.S.); Huntington, H. and Moore, S. (Editors). Ecological Applications 18(2): S126–S134.

4.  Hueffer, K., T.M. O'Hara, E.H. Follmann. 2011. Adaptation of Mammalian Host-Pathogen Interactions in a Changing Arctic Environment. Acta Veterinaria Scandinavica 53:17 www.actavetscand.com/content/53/1/17

5.  McGuire, A. D., L.G. Anderson, T.R. Christensen, S. Dallimore, L. Guo, D.J. Hayes, M. Heimann, T.D. Lorenson, R.W. MacDonald, and N. Roulet. 2009. Sensitivity of the carbon cycle in the Arctic to climate change. Ecological Monographs, 79(4): 523–555.