Linking Diet, Behavior, and Bioenergetics of a Migratory Waterbird to Evaluate Response to Wintering Ground Conditions

<p> Rivers in semi-arid regions are highly sensitive and pressured yet can support diverse assemblages of species. In central New Mexico, the Rio Grande (River) is the lifeblood of the Middle Rio Grande Valley (MRGV), a semi-arid region which maintains large urban and agricultural centers and is also the principal wintering area for the Rocky Mountain Population of greater sandhill cranes (<i>Antigone canadensis tabida</i>). Human-induced environmental change has transformed the MRGV and habitat availability prompting concerns for the population. To address these concerns, I investigated dietary and behavioral responses of sandhill cranes to the collection of features that function as winter habitat. In Chapter 1, I demonstrated a novel application of stable isotopes to evaluate dietary reliance of sandhill cranes on corn subsidies provisioned by natural resource agencies, estimated rates of carbon isotope incorporation in tissues of sandhill cranes, and estimated tissue-derived winter arrival dates of sandhill cranes. I found subsidized corn was the primary dietary component of sandhill cranes, rates of carbon isotope incorporation in sandhill crane tissues differed predictably by metabolic activity, and estimated tissue-derived arrival dates on wintering grounds approximated actual arrival dates. In Chapter 2, I advanced a hierarchical Bayesian framework for overcoming challenges and improving analysis of behavioral data frequently generated in animal behavior studies and used behavioral observations of sandhill cranes as a case study. In Chapter 3, I estimated energetic and temporal availability of corn subsidies and seasonal energy requirements of sandhill cranes. I found seasonal energetic requirements of the population are likely satisfied by corn subsides but not without strategic planning. In Chapter 4, I examined how current landscape and riverine configuration influenced patterns of diel habitat selection by sandhill cranes. Sandhill cranes avoided sources of anthropogenic disturbance, relied heavily on managed public land resources, and selected roosting locations in the Rio Grande with a wider channel, interspersion of sandbars and shallow water, and low channel bank vegetation. My research suggests sandhill cranes have coped with alterations that have led to current conditions in the MRGV, however, habitat-related resources will need to be managed adaptively as drivers of environmental change will undoubtedly influence future circumstances. </p><p>

Identiferoai:union.ndltd.org:PROQUEST/oai:pqdtoai.proquest.com:11010180
Date07 November 2018
CreatorsBoggie, Matthew Arthur
PublisherNew Mexico State University
Source SetsProQuest.com
LanguageEnglish
Detected LanguageEnglish
Typethesis

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