Natural and anthropogenic changes to the environment often cause demographic parameters to change, which can give rise to an unstable age, stage, or even spatial structure of a population. When population structure changes, the short-term transient dynamics, and even long-term stochastic dynamics, can be very different than when a constant environment and stable population structure is assumed. I examine demographic attributes that determine the effect of a changing or unstable population structure on a population’s dynamics, including the innate intertia (or momentum) that a single perturbtion can have on population abundance. From what I learn in modeling exercises, I then study the implications my findings have on the conservation and management of natural populations.

Life History Evolution in an Uncertain World

In addition to my research on population dynamics in stochastic environments, I also examine the implications of environmental uncertainty on life history evolution. Temporal variability in the environment can change demographic parameters, population structure, and eventually lead to the evolution of life history strategies that differ from those that are optimal in constant environments. For example, life-cycle delays and allocation of resources away from reproduction toward survival and longevity all decrease short-term fitness, but these bet-hedging strategies can drastically improve long-term fitness in an uncertaing environment. Collaborators and I use theoretical studies and long-term empirical data to better determine how life histories evolve in the real world that changes all the time.

Lesser Snow Goose Survival, Population Dynamics & Management

In collaboration with the Hudson Bay Project, I have begun research examining survival, dynamics, and management of the lesser snow goose population at LaPérouse Bay near Churchill, Manitoba. In particular, I am interested in how population density in early life indirectly affects physical & physiological development, which is known to affect survival of young snow geese, but may also affect rates of senescence later in life (for those making it past the stressful conditions of adolescence). Alongside predation (which mainly comes in the form of human harvest), these factors could have important impacts on population structure, dynamics, abundance, and thus the ways in which management should focus their efforts when trying to control population numbers. I am also interested in how the edge of the snow goose colony (i.e., the wavefront) moves over time in response to population density, and how this affects both the plant and animal communities.

Lesser Scaup Population Dynamics & Harvest Management

I continue to study the breeding ecology, demography, and population dynamics of lesser scaup in order to elucidate why the continental population is declining, which factors most influence change in population dynamics, and what can be done to manage them. I currently have a graduate student, Beth Ross, who is using the May Breeding Pairs Survey data to examine whether the occurrence of ‘breeding pairs’ relative to ‘groups’ has changed over time in the various biomes in which scaup nest. Beth is also integrating the BPS data with banding data and hunter survey data to assess the relative impacts of harvest, population density, as well as climate and habitat change on continental scaup population dynamics.

Other Research

I also enjoy collaborating with others on all things population biology, particularly the topics mentioned above. I try not to limit myself to wild vertebrates, and have enjoyed working with others on plant population biology and even human evolution.

Peer-Reviewed Publications

Dalgleish, H.J., D.N. Koons, and P.B. Adler. 2009. Can life history traits predict the response of forb populations to changes in climate variability. Journal of Ecology request reprint

Aubry, L.M. D.N. Koons, J.-Y. Monnat, and E. Cam. 2009. Consequences of recruitment decisions and heterogeneity on age-specific breeding success in a long lived seabird. Ecology 90:2491-2502. request reprint

Koons, D.N., R.D. Birkhead, S.M. Boback, M.I. Williams, and M.P. Greene. 2009. The effect of body size on cottonmouth (Agkistrodon piscivorus) survival, recapture probability, and behavior in an Alabama swamp. Herpetological Conservation and Biology URL: http://www.herpconbio.org/Volume_4/Issue_2/Koons_etal_2009.pdf

Koons, D.N., S. Pavard, A. Baudisch, and C.J.E. Metcalf. 2009. Is life-history buffering or lability adaptive in stochastic environments? Oikos 118:972-980. request reprint

Koons, D.N. 2009. Is harvest selecting for maladaptation in an increasingly variable world? Proceedings of the National Academy of Science, USA 106:E32. request reprint

Koons, D.N., C.J.E. Metcalf, and S. Tuljapurkar. 2008. Evolution of delayed reproduction in uncertain environments: a life history perspective. American Naturalist 172:797-805. request reprint

Pavard, S., D.N. Koons, and E. Heyer. 2007. The influence of maternal care in shaping human survival and fertility. Evolution 61:2801-2810. request reprint

Koons, D.N., R.R. Holmes, and J.B. Grand. 2007. Population inertia and its sensitivity to changes in vital rates and population structure. Ecology 88:2857-2867. request reprint

Metcalf, C.J.E., K. Hampson, and D.N. Koons. 2007. What happens if density increases? Conservation implications of population influx into refuges. Animal Conservation 10:478-486. request reprint

Metcalf, C.J.E., and D.N. Koons. 2007. Environmental uncertainty, autocorrelation and the evolution of survival. Proceedings of the Royal Society of London, B 274:2153-2160. request reprint

Koons, D.N., J.J. Rotella, D.W. Willey, M. Taper, R.G. Clark, S. Slattery, R.W. Brook, R.M. Corcoran, and J.R. Lovvorn. 2006. Lesser Scaup population dynamics: what can be learned from available data? Avian Conservation and Ecology - Écologie et conservation des oiseaux 1(3): 6. [online] URL: http://www.ace-eco.org/vol1/iss3/art6/

Koons, D.N., J.B. Grand, and J.M. Arnold. 2006. Population momentum across vertebrate life histories. Ecological Modelling 197:418-430. request reprint

Koons, D.N., R.F. Rockwell, and J.B. Grand. 2006. Population momentum: implications for wildlife management. Journal of Wildlife Management 70:19-26. request reprint

Koons, D.N., J.B. Grand, B. Zinner, and R.F. Rockwell. 2005. Transient population dynamics: relations to life history and initial population state. Ecological Modelling 185:283-297. request reprint

Koons, D.N., and J.J. Rotella. 2003. Have lesser scaup, Aythya affinis, reproductive rates declined in parkland Manitoba? Canadian Field Naturalist 117:582-588. request reprint

Koons, D.N., and J.J. Rotella. 2003. Comparative nesting success of sympatric lesser scaup and ring- necked duck. Journal of Field Ornithology 74:222-229. request reprint

Stephens, S.E., D.N. Koons, D.W. Willey, and J.J. Rotella. 2003. Effects of habitat fragmentation on avian nesting success: a review of the evidence at multiple spatial scales. Biological Conservation 115:101-110. request reprint

Koons, D.N. 2000. First record of brown-headed cowbird egg in a lesser scaup nest. Wilson Bulletin 112:554. request reprint

Technical Publications

Grand, J.B., D.N. Koons, J.M. Arnold, and D.V. Derksen. 2006. Modeling the recovery of avian populations. USGS Report to the Alaska Science Center.

Rockwell, R.F., E. Reed, K. Dufour, and D.N. Koons. 2006. Modeling the mid-continent population of lesser snow geese. An update to: Rockwell, R.F., E.G. Cooch, and S. Brault. 1997. Dynamics of the mid-continent population of lesser snow geese - Projected impacts of reductions in survival and fertility on population growth rates. Pages 73-100. In: B. Batt (ed) Arctic Ecosystems in Peril: Report of the Arctic Goose Habitat Working Group. Arctic Goose Joint Venture, Canadian Wildlife Service, Ottawa and US Fish and Wildlife Service, Washington, D.C.

Carlson, J., A. Craighead, P. Harmata, D. Koons, L. Oechsli, D. Ouren, E. Stackhouse, and B. Wilmer. 1999. Gallatin County fish and wildlife habitat. Montana State University, Bozeman, Montana.

Koons, D.N., R. Brooks, and D. Dolsen. 1998. Licensed angler assessment of the fisheries program: A report on the outcomes assessment project. in Montanans’ assessment of Montana Fish, Wildlife, and Parks programs. Montana Fish, Wildlife & Parks, Helena, Montana.

Prospective Students

My lab recently filled, but information will be posted here when positions become available

(if you have your own funding feel free to contact me)