Geology topics

Corrie C. Borgman

Publications and source records attributed to Corrie C. Borgman.

3 recordsLinked to original sources

USGS2025

Inferring Brown-Capped Rosy-Finch demography and breeding distribution trends from long-term wintering data in New Mexico

The three North American Rosy-Finch species (Brown-capped [ Leucosticte australis ], Black [ L. atrata ], and Gray-crowned [ L. tephrocotis ]) are among the most climate-threatened species in the United States. New Mexico is an important location for investigating the effects of climate change because it is the southernmost location in which Brown-capped Rosy-Finches breed and the southernmost location where all three Rosy-Finch species co-occur during winter. In the context of climate change, this range boundary is important to study because it is the first part of the range anticipated to cross a threshold of unsuitability for these species with increasing temperatures. Rosy-Finches are difficult to study during the breeding season due to the high elevation and remoteness of their breeding grounds; therefore, winter studies may lend insight into population trends and provide direction for conservation actions based on knowledge of the breeding origins of wintering birds. The goals of our study were to investigate long-term survival and migration trends from wintering Brown-capped Rosy-Finches in New Mexico and evaluate the efficacy of radio frequency identification (RFID)-equipped artificial feeders to monitor population trends. As of May 2025, we have conducted a robust design survival analysis on 22 years of mark-recapture data from a particular wintering site in New Mexico, assessed patterns in the breeding origins of individuals captured at this site using stable isotope analysis, and examined patterns in data collected via RFID. Our main findings from this study are that annual survival probability of Rosy-Finches wintering in New Mexico is low compared to that of other migratory passerines, that Brown-capped Rosy-Finches wintering in New Mexico likely originate from a variety of locations across their breeding range, and that RFID monitoring is useful in improving survival estimates in Rosy-Finches, particularly in short-term studies.

New Mexico↗

USGS2023

Ectoparasitism and energy infrastructure limit survival of preadult Golden Eagles in the Southern Great Plains

Much of the US Southern Great Plains (SGP) continues to undergo intensive energy development that could affect the region's Golden Eagles ( Aquila chrysaetos ), yet the species' population status there is unknown. During 2011–2020, we used satellite telemetry to assess annual survival rates and causes of mortality among 40 preadult (<3 yr of age) Golden Eagles in the SGP; 29 were monitored beginning at the late nestling stage and 11 immigrated into the SGP from western regions. For comparison we monitored 15 preadult Golden Eagles from nests in the Central Great Plains (CGP), where energy development was less extensive. We estimated survival rates by using a multi-state model in a Bayesian framework that accounted for probabilities of causes of death. Mean annual survival in the SGP during the preadult period was 0.060, versus 0.512 in the CGP and ∼0.7–0.9 reported elsewhere in the coterminous western USA. Mexican chicken bugs ( Haematosiphon inodorus ) were implicated in deaths of at least seven Golden Eagles during the ∼2-wk late nestling stage and in two deaths <3 mo after fledging. Energy infrastructure especially electrocutions accounted for 12 (57.1%) of 21 deaths of post-fledged preadults. Seven of 11 immigrant eagles died. Overall, probabilities of death of a Golden Eagle during the preadult period in the SGP due to Mexican chicken bugs and to electrocution were both 0.345. We estimated that the SGP population may be declining 9% annually due to poor recruitment; mitigation of underlying factors should be a priority for managing Golden Eagles in the western USA.

Colorado, Kansas, New Mexico, Oklahoma, Texas↗

USGS2018

A full annual-cycle conservation strategy for Sprague’s Pipit, Chestnut-collared and McCown’s Longspurs, and Baird’s Sparrow

Sprague’s Pipit ( Anthus spragueii ), Chestnut-collared Longspur ( Calcarius ornatus ), McCown’s Longspur ( Rhynchophanes mccownii ), and Baird’s Sparrow ( Centronyx bairdii ) [hereafter, “the Species”] are North American grassland-obligate songbirds whose populations have experienced significant annual population declines and are the focus of increasing conservation concern. The purpose of this strategy is to summarize current knowledge of the Species and identify priority research, monitoring and conservation actions required to improve their population status. Grasslands are among the most threatened ecosystems in the world with historic losses of 61-70% converted to other land uses, primarily cropland agriculture. Losses continue, with current conversion in the northern Great Plains occurring several times faster than grasslands can be protected. The Partners in Flight North American Landbird Conservation Plan (PIF NALCP) estimates current global populations of 900,000, 3,000,000, 600,000, and 2,000,000 for Sprague’s Pipit, Chestnut-collared Longspur, McCown’s Longspur, and Baird’s Sparrow, respectively. Over the period of 1967-2015, these populations have declined at -3.1, -4.2, -5.9 and -2.2% annually for estimated total losses of 78, 87, 94 and 65%, respectively. Habitat associations of breeding birds, especially at the local scale, represent the majority of the existing scientific literature on the Species’ biology. Landscape-scale associations are more poorly understood, and few studies have linked habitat, at any scale, to population vital rates. Increasing effort is focused on nonbreeding season and very little is known about migration. Current knowledge identifies three primary threats: 1) loss of native grasslands, 2) degradation and fragmentation of remaining native grasslands, and 3) disturbance inconsistent with needs of the Species. Top priorities for future research include: identification of population limiting factors, links between breeding habitat and demographics, identification of migratory habitat requirements, and identification of conditions promoting winter survival. Implementation strategies must focus on the protection, restoration, and enhancement (i.e., management) of grassland communities. Most imperative is the protection of remaining native grasslands from conversion to other uses. Actions supporting grass-based agriculture on privately-owned, native grasslands are paramount. These include incentive-based tools to support livestock grazing that benefits both priority birds and healthy ranching communities, which in turn prevent the conversion of native grasslands to cropland. Where cropland conversion has already taken place, conservation partners should work to continue and improve programs such as the Conservation Reserve Program (CRP) to restore and maintain permanent native cover. This strategy adopts the PIF NALCP objective, which is to reduce the rate of the Species’ decline in the first 10 years, then stabilize and ultimately increase the 2016 population by 5-15% over the subsequent 20 years. Ongoing monitoring programs such as the Breeding Bird Survey, Integrated Monitoring of Bird Conservation Regions, and eBird are critical for informing broadscale demographic and geographic trends for the Species. However, to achieve PIF NALCP goals, there is additional need for monitoring that links habitat conservation accomplishments to population performance within a strategic habitat conservation framework.

Report↗