Life Sciences Commons^™

Stable Isotopic Niche Predicts Fitness Of Prey In A Wolf–Deer System, C. T. Darimont, P. C. Paquet, T. E. Reimchen

Chris Darimont, Ph.D.

Interindividual variation in niche presents a potentially central object on which natural selection can act. This may have important evolutionary implications because habitat use governs a suite of selective forces encountered by foragers. In a free‐living native black‐tailed deer, Odocoileus hemionus, population from coastal British Columbia, we used stable isotope analysis to identify individual variation in foraging niche and investigated its relationship to fitness. Using an intragenerational comparison of surviving and nonsurviving O. hemionus over 2 years of predation by wolves, Canis lupus, we detected resource‐specific fitness. Individuals with isotopic signatures that suggested they foraged primarily in cedar ( …

African Penguins Follow The Gaze Direction Of Conspecifics, Christian Nawroth, Livio Favaro

Christian Nawroth, Ph.D.

Economic Impact Of Double-Crested Cormorant, Phalacrocorax Auritus, Depredation On Channel Catfish, Ictalurus Punctatus,Aquaculture In Mississippi, Usa, Brian S. Dorr, Loren W. Burger, Scott C. Barras, Kristina Casscles Godwin

Brian S Dorr

The Yazoo River Basin of Mississippi, USA, supports the largest concentration of hectares devoted to channel catfish, Ictalurus punctatus, aquaculture production in North America. The Yazoo Basin also supports large numbers of resident, wintering and migrating fish-eating birds, with the Double-crested Cormorant, Phalacrocorax auritus, implicated as the most serious depredating species. We used data from aerial surveys of numbers and distribution of cormorants in the Yazoo Basin and on commercial catfish ponds during winters (November–April) 2000–2001 and 2003–2004 to refine estimates of regional economic losses due to cormorant depredation. In both periods, the greatest monthly estimates of cormorant foraging occurred …

Double-Crested Cormorant Distribution On Catfish Aquaculture In The Yazoo River Basin Of Mississippi, Brian S. Dorr, Loren W. Burger, Scott C. Barras, Kristina Casscles Godwin

Brian S Dorr

No abstract provided.

Management Of Double-Crested Cormorants To Improve Sport Fisheries In Michigan: Three Case Studies, Brian S. Dorr, Shauna L. Hanisch, Peter H. Butchko, David G. Fielder

Brian S Dorr

No abstract provided.

Evaluation Of Harassment Of Migrating Double-Crested Cormorants To Limit Depredation On Selected Sport Fisheries In Michigan, Brian S. Dorr, Ashley Moerke, Michael Bur, Chuck Bassett, Tony Aderman, Dan Traynor, Russell D. Singleton, Peter H. Butchko, Jimmy D. Taylor

Brian S Dorr

No abstract provided.

Differential Consumption Of Four Aphid Species By Four Lady Beetle Species, Christy Finlayson, Andrei Alyokhin, Serena Gross, Erin Porter

Andrei Alyokhin

The acceptability of four different aphid species Macrosiphum albifrons (Essig), Macrosiphum euphorbiae (Thomas), Macrosiphum pseudorosae Patch, and Myzus persicae (Sulzer) (Hemiptera: Aphididae), as prey for four lady beetle species, one native species Coccinella trifasciata L, and three non-native Coccinella septempunctata L, Harmonia axyridis Pallas, Propylea quatuordecimpunctata L (Coleoptera: Coccinellidae) were tested in the laboratory. The relative field abundance of adults of the same lady beetle species on host vegetation, Lupinus polyphyllus Lindley (Fabales: Fabaceae), Solanum tuberosum L (Solanales: Solanaceae), and Rosa multiflora Thunberg (Rosales: Rosaceae), both with and without aphids present was also observed. In the laboratory, H. axyridis generally …

Captive Double-Crested Cormorant Phalacrocorax Auritus Predation On Channel Catfish Ictalurus Punctatus Fingerlings And Its Influence On Single-Batch Cropping Production, Brian S. Dorr

Brian S Dorr

Abstract.-We studied the effect of captive double-crested cormorant Phalacrocorax auritus predation on channel catfish Ictalurus punctatus inventories from research ponds with and without alternative prey during the years 1998-2000. In 1998, predation by two groups of captive cormorants on ponds without alternative prey produced inventory reductions relative to a control pond that were equivalent to 10.2 (516 g) and I 0.5 (608 g) catfish/bird per d. In 1999 and 2000 individual cormorants foraging on 0.02-ha pond halves for I 0 d (500 cormorant d/ha) stocked with both catfish and golden shiners Notemigonus crysoleucas produced inventory reductions at harvest (7.5 mo …

Evaluation Of A Methyl Anthranilate-Based Bird Repellent: Toxicity To Channel Catfish Ictalurus Punctatus And Effect On Great Blue Heron Ardea Herodias Feeding Behavior, Brian S. Dorr, Larry Clark, Igor Mezine

Brian S Dorr

No abstract provided.

Behavior And Ecological Interactions Of Larval Odonata, Clay L. Pierce, Philip H. Crowley, Dan M. Johnson

Clay L. Pierce

Enallagma aspersum and E. traviatum (Odonata: Coenagrionidae) are the most abundant larval odonates in Bays Mountain Park (Sullivan County, Tennessee, USA), although their spatial distributions are essentially nonoverlapping. E. traviatum coexists with insectivorous fish in a small lake, whereas E. aspersum is restricted to a small fishless pond nearby. Behavioral observations revealed that E. aspersum larvae were more active than E. traviatum, and tended to occupy more conspicuous positions. E. aspersum also engaged in more confrontations than E. traviatum, especially at higher density. In laboratorye xperimentsw ith juvenile bluegills( Lepomism acrochirusa) s predators,E . aspersum larvae were more vulnerable to …