scholarly journals Macrobenthic prey and physical habitat characteristics in a western Gulf sturgeon population: differential estuarine habitat use patterns

2013 ◽  
Vol 22 (2) ◽  
pp. 159-174 ◽  
Author(s):  
MS Peterson ◽  
JM Havrylkoff ◽  
PO Grammer ◽  
PF Mickle ◽  
WT Slack ◽  
...  
2015 ◽  
Vol 145 (1) ◽  
pp. 27-43 ◽  
Author(s):  
Mark S. Peterson ◽  
Jeanne-Marie Havrylkoff ◽  
Paul O. Grammer ◽  
Paul F. Mickle ◽  
William T. Slack

2020 ◽  
Vol 77 (3) ◽  
pp. 611-624
Author(s):  
Jonathan Hegna ◽  
Kim Scribner ◽  
Edward Baker

Identifying movement and habitat use patterns is essential for fish passage efforts and the conservation of threatened species. We used acoustic telemetry to track the movements of 44 juvenile lake sturgeon (Acipenser fulvescens) throughout Kleber Reservoir in northern Michigan. On average, lake sturgeon moved 502 m between telemetry positions, with age-2 lake sturgeon moving longer distances than age-1 lake sturgeon. Areas with high numbers of lake sturgeon detections were clustered near the forebay, while zones with low numbers of detections were clustered toward the head of the reservoir. Analyses showed that 66.4% of the variance in habitat use could be explained by physical habitat features. Reservoir areas with ample deepwater habitat, fine soft substrates, and limited macrophyte vegetation were the most frequently occupied and, thus, may provide suitable habitat conditions to support juvenile lake sturgeon. We observed that 54.4% of the age-1 and 52.8% of the age-2 lake sturgeon stocked into Kleber Reservoir were entrained. Reservoir size, morphology, and the location of suitable habitat in relation to hydroelectric infrastructure may be key factors that affect entrainment rates.


2012 ◽  
Vol 3 (1) ◽  
pp. 89-97 ◽  
Author(s):  
David G. Krementz ◽  
Sarah E. Lehnen ◽  
Jason D. Luscier

Abstract The Big Woods of eastern Arkansas contain some of the highest densities of woodpeckers recorded within bottomland hardwood forests of the southeastern United States. A better understanding of habitat use patterns by these woodpeckers is a priority for conservationists seeking to maintain these high densities in the Big Woods and the Lower Mississippi Alluvial Valley as a whole. Hence, we used linear mixed-effects and linear models to estimate the importance of habitat characteristics to woodpecker density in the Big Woods during the breeding seasons of 2006 and 2007 and the winter of 2007. Northern flicker Colaptes auratus density was negatively related to tree density both for moderate (>25 cm diameter at breast height) and larger trees (>61 cm diameter at breast height). Red-headed woodpeckers Melanerpes erythrocephalus also had a negative relationship with density of large (>61 cm diameter at breast height) trees. Bark disfiguration (an index of tree health) was negatively related to red-bellied woodpecker Melanerpes carolinus and yellow-bellied sapsucker Sphyrapicus varius densities. No measured habitat variables explained pileated woodpecker Dryocopus pileatus density. Overall, the high densities of woodpeckers observed in our study suggest that the current forest management of the Big Woods of Arkansas is meeting the nesting, roosting, and foraging requirements for these birds.


2017 ◽  
Vol 23 (10) ◽  
pp. 4045-4057 ◽  
Author(s):  
Ross E. Boucek ◽  
Michael R. Heithaus ◽  
Rolando Santos ◽  
Philip Stevens ◽  
Jennifer S. Rehage

Author(s):  
Daniel Danilewicz ◽  
Eduardo R. Secchi ◽  
Paulo H. Ott ◽  
Ignacio B. Moreno ◽  
Manuela Bassoi ◽  
...  

The patterns of habitat use by the franciscana dolphins (Pontoporia blainvillei) along its distribution are poorly known. This study investigates the patterns of habitat use with respect to depth for 181 individuals of different age, size, gender and reproductive condition off Rio Grande do Sul, southern Brazil. The results reveal that franciscanas are very homogeneously distributed according to depth. Individuals from all lengths utilize nearly the entire range of depths of the surveyed area. Larger or older animals do not use deeper waters than younger animals, indicating that body size and age are not limiting factors for franciscanas that occupy deeper or offshore waters. Gestation seems to not cause a change in the distribution of females. Although the sex-ratio of the overall data did not vary from 1:1 in different depth intervals, a small-scale comparison between the northern and southern coast demonstrated the existence of some kind of sexual segregation. Franciscana by-catch in Rio Grande do Sul is not sustainable and it is agreed that management procedures are needed. Nevertheless, the available data on species distribution do not allow the designing of a protected area in order to minimize the by-catches of a particular sex/reproductive class.


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