Spatial and temporal patterns of predation of simulated sage grouse nests at high and low nest densities: an experimental study

1995 ◽  
Vol 73 (5) ◽  
pp. 819-825 ◽  
Author(s):  
Neal D. Niemuth ◽  
Mark S. Boyce
Keyword(s):  
Nest Predation ◽  
Defense Mechanisms ◽  
Prey Capture ◽  
Centrocercus Urophasianus ◽  
Site Location ◽  
Spatial And Temporal Patterns ◽  
Sage Grouse ◽  
Nest Location ◽  
Density Dependent ◽  
Predation Intensity

We examined patterns of predation on 252 simulated sage grouse (Centrocercus urophasianus) nests placed at two densities around six active leks in southeastern Wyoming, U.S.A. Predation intensity, as measured by the frequency of multiple-nest predation events, was significantly greater at high-density sites, implying enhanced prey capture (functional and (or) numerical response) by predators. Significant spatial aggregation of nest predation further implies enhanced prey capture by predators at high prey densities. Predation varied significantly among sites, but there were no significant first-order differences in predation between densities. Predation was also significantly affected by year–density and site–year–density interactions. Several factors, including nest cover, prey defense mechanisms, study site location, nest location, year, search methods of predators, number of predators, and random encounter may inhibit or confound density-dependent nest predation. Enhanced prey capture provides a mechanism for density-dependent population regulation.

Greater Sage-Grouse (Centrocercus urophasianus)

1999 ◽  
Author(s):  
Michael A. Schroeder ◽  
Jessica R. Young ◽  
Clait E. Braun
Keyword(s):  
Centrocercus Urophasianus ◽  
Sage Grouse

scholarly journals Field Methods for Translocating Female Greater Sage‐Grouse ( Centrocercus urophasianus ) with their Broods

2021 ◽  
Author(s):  
Mary B. Meyerpeter ◽  
Kade D. Lazenby ◽  
Peter S. Coates ◽  
Mark A. Ricca ◽  
Steven R. Mathews ◽  
...  
Keyword(s):  
Centrocercus Urophasianus ◽  
Sage Grouse ◽  
Field Methods

Effects of power lines on habitat use and demography of greater sage-grouse (Centrocercus urophasianus)

2018 ◽  
Vol 200 (1) ◽  
pp. 1-41 ◽  
Author(s):  
Daniel Gibson ◽  
Erik J. Blomberg ◽  
Michael T. Atamian ◽  
Shawn P. Espinosa ◽  
James S. Sedinger
Keyword(s):  
Habitat Use ◽  
Centrocercus Urophasianus ◽  
Power Lines ◽  
Sage Grouse

Sexual Dichromatism in Birds: Importance of Nest Predation and Nest Location for Females Versus Males

Evolution ◽  
1996 ◽  
Vol 50 (6) ◽  
pp. 2454 ◽  
Author(s):  
Thomas E. Martin ◽  
Alexander V. Badyaev
Keyword(s):  
Nest Predation ◽  
Sexual Dichromatism ◽  
Nest Location

Can Reliable Sage-Grouse Lek Counts Be Obtained Using Aerial Infrared Technology?

2013 ◽  
Vol 4 (2) ◽  
pp. 386-394 ◽  
Author(s):  
Gifford L. Gillette ◽  
Peter S. Coates ◽  
Steven Petersen ◽  
John P. Romero
Keyword(s):  
Infrared Camera ◽  
Centrocercus Urophasianus ◽  
Management Tool ◽  
Breeding Period ◽  
Sage Grouse ◽  
Remote Areas ◽  
Infrared Technology ◽  
Infrared Surveys ◽  
Infrared Cameras ◽  
Infrared Techniques

Abstract More effective methods for counting greater sage-grouse (Centrocercus urophasianus) are needed to better assess population trends through enumeration or location of new leks. We describe an aerial infrared technique for conducting sage-grouse lek counts and compare this method with conventional ground-based lek count methods. During the breeding period in 2010 and 2011, we surveyed leks from fixed-winged aircraft using cryogenically cooled mid-wave infrared cameras and surveyed the same leks on the same day from the ground following a standard lek count protocol. We did not detect significant differences in lek counts between surveying techniques. These findings suggest that using a cryogenically cooled mid-wave infrared camera from an aerial platform to conduct lek surveys is an effective alternative technique to conventional ground-based methods, but further research is needed. We discuss multiple advantages to aerial infrared surveys, including counting in remote areas, representing greater spatial variation, and increasing the number of counted leks per season. Aerial infrared lek counts may be a valuable wildlife management tool that releases time and resources for other conservation efforts. Opportunities exist for wildlife professionals to refine and apply aerial infrared techniques to wildlife monitoring programs because of the increasing reliability and affordability of this technology.

scholarly journals Spatial Distribution of Greater Sage-Grouse Nests in Relatively Contiguous Sagebrush Habitats

The Condor ◽  
2005 ◽  
Vol 107 (4) ◽  
pp. 742-752 ◽  
Author(s):  
Matthew J. Holloran ◽  
Stanley H. Anderson
Keyword(s):  
Radio Telemetry ◽  
Centrocercus Urophasianus ◽  
Spatial Arrangement ◽  
Population Viability ◽  
Prey Detection ◽  
Population Declines ◽  
Sage Grouse ◽  
Nesting Habitat ◽  
Nesting Site ◽  
Low Probability

Abstract Degradation of nesting habitat has been proposed as a factor contributing to Greater Sage-Grouse (Centrocercus urophasianus) population declines throughout North America. Delineating suitable nesting habitat across landscapes with relatively contiguous sagebrush cover is difficult but important to identify areas for protection. We used radio-telemetry to locate Greater Sage-Grouse nests in relatively contiguous sagebrush habitats in Wyoming to investigate the spatial arrangement of nests relative to lek and other nest locations. Nest distributions were spatially related to lek location within 3 and 5 km of a lek, and a 5-km buffer included 64% of the nests. There was no relationship between lek size and lek-to-nest distance, suggesting that accurate population trend evaluation might require lek surveys in addition to lek counts. Closest known lek-to-nest distance was greater for successfully hatched compared to destroyed nests, and closely spaced nests tended to experience lower success and have higher probabilities of both nests experiencing the same fate compared to isolated nests, suggesting that a mechanism of enhanced prey detection occurred at higher nest densities. A low probability that a given individual's consecutive-year nest spacing occurred randomly suggested nesting site-area fidelity. Although a grouped pattern of nests occurred within 5 km of a lek, the proportion of nesting females located farther than 5 km could be important for population viability. Managers should limit strategies that negatively influence nesting habitat regardless of lek locations, and preserve adequate amounts of unaltered nesting habitat within treatment boundaries to maintain nest dispersion and provide sites for philopatric individuals.

scholarly journals Genetic mark‐recapture analysis of winter faecal pellets allows estimation of population size in Sage Grouse Centrocercus urophasianus

Ibis ◽  
2019 ◽  
Vol 162 (3) ◽  
pp. 749-765 ◽  
Author(s):  
Jessica E. Shyvers ◽  
Brett L. Walker ◽  
Sara J. Oyler‐McCance ◽  
Jennifer A. Fike ◽  
Barry R. Noon
Keyword(s):  
Population Size ◽  
Centrocercus Urophasianus ◽  
Sage Grouse ◽  
Mark Recapture ◽  
Faecal Pellets

Sexual and subspecific variation in the numbers of rectrices of blue grouse

1991 ◽  
Vol 69 (1) ◽  
pp. 134-140 ◽  
Author(s):  
Fred C. Zwickel ◽  
Mark A. Degner ◽  
Donald T. McKinnon ◽  
David A. Boag
Keyword(s):  
Distinct Group ◽  
Centrocercus Urophasianus ◽  
Small Sample ◽  
Hybrid Population ◽  
Sage Grouse ◽  
Modal Number ◽  
The North ◽  
Dendragapus Obscurus ◽  
Coastal Birds ◽  
Males And Females

We examined numbers of rectrices of all subspecies of blue grouse (Dendragapus obscurus), determined from our own studies and reported in the literature. Approximately 8% of all birds had an uneven number of rectrices, with no difference between males and females. More birds from a presumed subspecific "hybrid" population had uneven numbers of rectrices than those from "nonhybrid" samples. Of North American tetraonines, sage grouse (Centrocercus urophasianus) and blue grouse appear most variable in this character. Within subspecies, males and females had the same modal numbers of rectrices. The sexes differed, however, in the overall distribution of numbers of rectrices; most birds with submodal numbers were females and most birds with supermodal numbers, males. Males and females in one hybrid population differed in modal numbers of rectrices: males 20, and females 18. Eighty per cent of all coastal blue grouse had 18 rectrices, with no differences among subspecies. In contrast, all interior subspecies differed from each other. The two northern interior subspecies, D. o. pallidus and D. o. richardsonii, had modes of 20 rectrices, with that for pallidus weaker than that for richardsonii (70 and 81% modal, respectively). Dendragapus obscurus obscurus had a mode of 18 rectrices, not different from that for coastal birds. A small sample of D. o. oreinus was equally divided between birds with 18 and 20 rectrices, suggesting relationships with D. o. pallidus to the north and D. o. obscurus to the east. Northern interior blue grouse emerge as a distinct group with respect to modal number of rectrices, which parallels the pattern for the presence or absence of tail bands. Based on these two characteristics, coastal blue grouse appear more closely related to southern interior than to northern interior subspecies. The blue grouse is the only tetraonine with clear evidence of subspecific variation in numbers of rectrices.

scholarly journals Jasmonate-independent regulation of digestive enzyme activity in the carnivorous butterwort Pinguicula × Tina

2020 ◽  
Vol 71 (12) ◽  
pp. 3749-3758 ◽  
Author(s):  
Ondřej Kocáb ◽  
Jana Jakšová ◽  
Ondřej Novák ◽  
Ivan Petřík ◽  
René Lenobel ◽  
...  
Keyword(s):  
Jasmonic Acid ◽  
Enzyme Activities ◽  
Digestive Enzymes ◽  
Defense Mechanisms ◽  
Prey Capture ◽  
Digestive Enzyme ◽  
Carnivorous Plants ◽  
Alpha Amylase ◽  
Jasmonate Signaling ◽  
Digestive Enzyme Activities

Abstract Carnivorous plants within the order Caryophyllales use jasmonates, a class of phytohormone, in the regulation of digestive enzyme activities. We used the carnivorous butterwort Pinguicula × Tina from the order Lamiales to investigate whether jasmonate signaling is a universal and ubiquitous signaling pathway that exists outside the order Caryophyllales. We measured the electrical signals, enzyme activities, and phytohormone tissue levels in response to prey capture. Mass spectrometry was used to identify proteins in the digestive secretion. We identified eight enzymes in the digestive secretion, many of which were previously found in other genera of carnivorous plants. Among them, alpha-amylase is unique in carnivorous plants. Enzymatic activities increased in response to prey capture; however, the tissue content of jasmonic acid and its isoleucine conjugate remained rather low in contrast to the jasmonate response to wounding. Enzyme activities did not increase in response to the exogenous application of jasmonic acid or coronatine. Whereas similar digestive enzymes were co-opted from plant defense mechanisms among carnivorous plants, the mode of their regulation differs. The butterwort has not co-opted jasmonate signaling for the induction of enzyme activities in response to prey capture. Moreover, the presence of alpha-amylase in digestive fluid of P. × Tina, which has not been found in other genera of carnivorous plants, might indicate that non-defense-related genes have also been co-opted for carnivory.

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