Weekly Highlights for 4-14-2017
Marbled Murrelet Poster to be Included in USFWS Conference
Oregon State University student Lorraine K. Waianuhea, mentored by USGS ecologist Joan Hagar, will present a poster about “Corvid Response to Forest Thinning in the Willamette National Forest: Implications for the Conservation of the Marbled Murrelet” at the USFWS Science of the Service Symposium in Portland, Oregon on April 24.
USGS to Discuss eDNA at Idaho NOAA Meeting
USGS ecologist David Pilliod will give a talk about Chinook salmon eDNA research in the Okanagon Basin at the NOAA Snake Basin Salmon and Steelhead Science Meeting and Workshop in Boise, Idaho on April 18-19.
Integrating Count and Detection/Nondetection Data to Model Population Dynamics
Estimating demographic rates, population abundance, and trends is a universal objective in conservation biology, but traditional mark-recapture studies of individuals are costly, logistically difficult, and spatially limited. Researchers developed a modeling approach that allows for estimation of demographic traits and abundance by combining different types of “unmarked” data typically obtained during surveys of a species – presence/absence (detection/nondetection) data and site-specific counts of individuals. They demonstrate the utility of the model using a series of simulations, then apply the model to different types of survey data collected on a growing population of barred owls in the Pacific Northwest to examine factors influencing population trends from 1995 to 2016. Their approach will be useful for survey design and incorporating historical or citizen science data into more contemporary analyses to understand how demographic rates drive population abundance.
Zipkin, E.F., Rossman, S., Yackulic, C.B., Wiens, J.D., Thorson, J.T., Davis, R.J., Grant, E.H., 2017, Integrating count and detection-nondetection data to model population dynamics: Ecology, p. online, http://dx.doi.org/10.1002/ecy.1831. [Details]
Polygamy Slows Down Population Divergence in Shorebirds
Sexual selection may promote speciation since competition for mates can favor specific individuals more desirable for reproduction, leading to reproductive isolation. Alternatively, sexual selection may also hinder speciation since polygamous individuals access additional mates, increasing breeding dispersal and promoting genetic diversity within a species. High breeding dispersal should increase gene flow, reducing species differentiation, which can be a proxy for population divergence. Examining genetic data from different populations of 136 shorebird species, researchers found that polygamous species display significantly less genetic structure, and showed fewer subspecies, than monogamous species. By contrast, migratory behavior neither predicted genetic differentiation nor subspecies richness. Results suggest that dispersal associated with polygamy may facilitate gene flow and limit population divergence. Therefore, intense sexual selection, as occurs in polygamous species, may inhibit rather than promote speciation in shorebirds.
D’Urban Jackson, J., dos Remedios, N., Maher, K., Zefania, S., Haig, S.M., Oyler-McCance, S.J., Blomqvist, D., Burke, T., Bruford, M.W., Székely, T., Küpper, C., 2017, Polygamy slows down population divergence in shorebirds: Evolution, p. online, http://dx.doi.org/10.1111/evo.13212. [Details]
Reduced Snowpack and Warming Effects on Montane Meadow Plants
Shifts in vegetation phenology, or the timing of seasonal life-cycle changes in plants, may have consequences for foraging or pollinating animals and insects. To investigate how changes in climate can affect phenology, growth, and frost response of forbs, researchers removed snow and experimentally warmed a high-elevation meadow over two years in the Rocky Mountains. The forbs studied are important for pollinators, and included arrowleaf balsamroot, which emerges and flowers early, and buckwheat, a late-season flowering plant. Removing snow accelerated arrowleaf balsamroot green-up and flowering by several days, which led to frost damage of its flowers. Snow removal advanced buckwheat green-up more than two weeks, and also increased height of buckwheat appreciably. Warming increased height of arrowleaf balsamroot and decreased frost damage to its flowers. Results suggest that timing of snowmelt has a greater impact on phenology, growth, and floral survival traits than warming. These shifts could cause uncoupling in nectar availability and timing of foraging.
Sherwood, J.A., Debinski, D.M., Caragea, P.C., Germino, M.J., 2017, Effects of experimentally reduced snowpack and passive warming on montane meadow plant phenology and floral resources: Ecosphere, v. 8, no. 3, p. e01745, http://dx.doi.org/10.1002/ecs2.1745. [Details]
A Proactive Response to Addressing Infectious Wildlife Diseases
Actions in response to infectious wildlife diseases are often considered only after a disease has been detected. Reactive management approaches may not be cost-effective and can limit the potential for control. An international team of researchers highlights the utility of developing a proactive approach to address the potential introduction of the fungal pathogen Batrachochytrium salamandrivorans – or Bsal – into the United States, which can be fatal to salamanders. They identify immediate coordinating activities that can engage researchers and decision-makers in proactive management. The authors advocate an approach to frame, create, and evaluate trade-offs among proactive (pre-invasion) and reactive (post-invasion) management strategies and potential costs of delayed action. Their strategy can serve as an example for other emerging infectious diseases.
Grant, E.H., Muths, E., Katz, R.A., Canessa, S., Adams, M.J., Ballard, J.R., Berger, L., Briggs, C.J., Coleman, J., Gray, M.J., Harris, M.C., Harris, R.N., Hossack, B., Huyvaert, K.P., Kolby, J.E., Lips, K.R., Lovich, R.E., McCallum, H.I., Mendelson III, J.R., Nanjappa, P., Olson, D.H., Powers, J.G., Richgels, K.L., Russell, R.E., Schmidt, B.R., Spitzen-van der Sluijs, A., Watry, M., Woodhams, D.C., White, C.L., 2017, Using decision analysis to support proactive management of emerging infectious wildlife diseases: Frontiers in Ecology and the Environment, p. online, http://dx.doi.org/10.1002/fee.1481. [Details]
Collaborative Research Presented at Geographers Meeting
A poster titled “Centennial-scale reductions in nitrogen availability in temperate forests of the United States” was presented at the annual meeting of the American Association of Geographers in Boston, Massachusetts, April 5-9.
Science Daily Highlights Polygamous Bird Study
A paper written by an international team of researchers that included USGS researchers was featured on Science Daily’s website on April 10. The paper documented that polygamous plover species display significantly less genetic structure than monogamous species, which may decrease the chance that polygamous bird populations will diversify into new species over time.
Sierra Magazine to Feature USGS Golden Eagle Migration Study
Jason Daley, who writes for a natural history column for Sierra magazine, contacted USGS wildlife biologist Todd Katzner on April 7. Daley is interested in writing a story about a recently published paper co-authored by Katzner about how weather and experience affects golden eagle migration.