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Wildlife Service (wildlife + service)
Selected AbstractsTypological thinking and the conservation of subspecies: the case of the San Clemente Island loggerhead shrikeDIVERSITY AND DISTRIBUTIONS, Issue 4 2000Michael A. Patten Abstract. ,Hybridization with closely related taxa poses a significant threat to endangered subspecies (e.g. outbreeding depression, inbreeding) and confounds efforts to manage and conserve these taxa through a loss of taxonomic identity, in part because of the practical necessity of defining subspecies in a typological manner. We examined nine morphological characters in 167 post-juvenile museum specimens to determine if loggerhead shrikes Lanius ludovicianus Linnaeus 1766 on San Clemente Island (off the coast of California) remain diagnosable as L. l. mearnsi Ridgway (1903); an island endemic listed as endangered by the United States Fish and Wildlife Service. Four recent shrike specimens from the island were compared to historical specimens using a bivariate scatter plot and a discriminant function (the latter was used to classify recent specimens post hoc). The few recent specimens were not diagnosable as L. l. mearnsi, but instead appear to be intergrades between L. l. mearnsi and L. l. anthonyi Mearns 1898 (the subspecies endemic to Santa Cruz, Santa Catalina, Santa Rosa and Anacapa islands), and are perhaps closer to pure anthonyi. Our data and the species' natural history and distribution suggest that shrikes currently on San Clemente Island are the result of genetic ,swamping' of mearnsi by anthonyi. Under a necessarily typological definition of a subspecies, it is evident that mearnsi is probably no longer diagnosable. However, we conclude that protection of the entire Channel Islands population of the loggerhead shrike would be the best management strategy, as the species has declined drastically throughout the islands. [source] Conservation and collection efforts for the endangered Alabama sturgeon (Scaphirhynchus suttkusi)JOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2007S. J. Rider Summary The Alabama sturgeon (Scaphirhynchus suttkusi) is the rarest and most endangered sturgeon species in North America. Over an 8-year period, the Alabama Division of Wildlife and Freshwater Fisheries, U.S. Army Corps of Engineers, and U.S. Fish and Wildlife Service cumulatively expended 2447 man-days in efforts to collect Alabama sturgeon broodstock in an attempt to initiate a conservation propagation program. Out of nearly 29 000 fishes collected between March 1997 and May 2005, only five were Alabama sturgeon. Attempts to spawn and propagate these sturgeons were unsuccessful, and all have since died in captivity. In context with past collection efforts and anecdotal accounts, these results indicate that the Alabama sturgeon is becoming increasingly rare with the passage of time. Although there is evidence that some level of recruitment continued to occur in the Alabama River during the past decade, the increasing rarity of Alabama sturgeon suggests that mortality rates are exceeding recruitment. [source] USE OF THE DELPHI METHOD IN RESOLVING COMPLEX WATER RESOURCES ISSUES,JOURNAL OF THE AMERICAN WATER RESOURCES ASSOCIATION, Issue 1 2003Jonathan G. Taylor ABSTRACT: The tri-state river basins, shared by Georgia, Alabama, and Florida, are being modeled by the U.S. Fish and Wildlife Service and the U.S. Army Corps of Engineers to help facilitate agreement in an acrimonious water dispute among these different state governments. Modeling of such basin reservoir operations requires parallel understanding of several river system components: hydropower production, flood control, municipal and industrial water use, navigation, and reservoir fisheries requirements. The Delphi method, using repetitive surveying of experts, was applied to determine fisheries' water and lake-level requirements on 25 reservoirs in these interstate basins. The Delphi technique allowed the needs and requirements of fish populations to be brought into the modeling effort on equal footing with other water supply and demand components. When the subject matter is concisely defined and limited, this technique can rapidly assess expert opinion on any natural resource issue, and even move expert opinion toward greater agreement. [source] Rosette Recruitment of a Rare Endemic Forb (Gaura neomexicana Subsp. coloradensis) with Canopy Removal of Associated SpeciesRESTORATION ECOLOGY, Issue 1 2002Linda M. Munk Abstract Gaura neomexicana subsp. coloradensis Munz (Onagraceae), (Colorado butterfly plant), a short-lived perennial forb, became listed as a threatened species by the U.S. Fish and Wildlife Service in October 2000 because of its small global range and population size. This endemic subspecies consists of only 18 extant populations within southeastern Wyoming, southwestern Nebraska, and northeastern Colorado. Wyoming occurrences are on private land with the exception of three occurrences on F. E. Warren Air Force Base, near Cheyenne. Gaura neomexicana subsp. coloradensis may be displaced by many competitors, including Cirsium arvense (L.) Scop. (Canada thistle), an invasive, noxious weed. In June 1998, three G. neomexicana subsp. coloradensis populations were examined for rosette establishment in the presence of and after removal of associated species. The four study treatments removed: (1) Cirsium arvense, (2) grass and forb canopy and associated litter, (3) grass and forb canopy, litter, and C. arvense, and (4) no removal of associated plant species (control). Mature G. neomexicana subsp. coloradensis plants were evaluated for height, number of leaves, and capsule production. The mature plant characteristics monitored in 1998 were not good indicators of subsequent G. neomexicana subsp. coloradensis rosette densities in the following spring. Recruitment was assessed by counting new rosettes in the fall 1999. Although both G. neomexicana subsp. coloradensis and the exotic C. arvense have comparable habitat, removal of C. arvense did not increase G. neomexicana subsp. coloradensis vegetative growth, seed capsule production, or rosette density. Removal of other forbs, grass, and litter, however, increased G. neomexicana subsp. coloradensis rosette density in the following two years, indicating that canopy removal of associated species can enhance rosette establishment of this rare native. The accumulation of dense vegetative cover and litter associated with the absence of herbivory and fire may contribute to the decline of rare species in rich riparian habitats. Return of herbivory and fire in mesic sites to reduce standing biomass accumulations should be considered in restoring recruitment potential to rare monocarpic species. [source] Extent and possible conservation implications of fish use for research, testing and education in North AmericaAQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 6 2006Melissa Grey Abstract 1.Fish species are used globally for fundamental research, product and environmental testing, and education, but this use has not hitherto been documented. The number of fish used for research and education in North America currently represents approximately one-quarter of all animal use for these purposes; only mice are used in higher numbers. Data from the Canadian Council on Animal Care, various animal care committees from Canadian universities, and the United States Fish and Wildlife Service are collated and summarized. 2.In Canada nearly a half a million fish were used for research and education each year from 1996 to 2001. We estimated that the United States used over four times that amount for the same purposes, totalling approximately 2.8 million fish each year. 3.At least 100 fish species, representing 27 taxonomic orders, were used for research and education in North America from 1996 to 2001. Close to one-third of the species had life-history characteristics that might make them particularly susceptible to over-exploitation. This potential vulnerability, coupled with data from animal care facilities in Canada suggesting that nearly half of all fish used for research and education were wild-caught, should prompt further documentation of such fish uses in order to assess their sustainability. Copyright © 2006 John Wiley & Sons, Ltd. [source] Using faecal DNA sampling and GIS to monitor hybridization between red wolves (Canis rufus) and coyotes (Canis latrans)MOLECULAR ECOLOGY, Issue 8 2003J. R. Adams Abstract The US Fish and Wildlife Service's (USFWS) Red Wolf Recovery Program recognizes hybridization with coyotes as the primary threat to red wolf recovery. Efforts to curb or stop hybridization are hampered in two ways. First, hybrid individuals are difficult to identify based solely on morphology. Second, managers need to effectively search 6000 km2 for the presence of coyotes and hybrids. We develop a noninvasive method to screen large geographical areas for coyotes and hybrids with maternal coyote ancestry by combining mitochondrial DNA sequence analysis of faeces (scat) and geographic information system (GIS) technology. This method was implemented on the Alligator River National Wildlife Refuge (1000 km2) in northeastern North Carolina. A total of 956 scats were collected in the spring of 2000 and 2001 and global positioning system (GPS) coordinates were recorded. Seventy-five percent of the scats were assigned to species and five coyote/hybrid scats were detected. Placement of scat location coordinates on a map of the experimental population area revealed that four of the coyote/hybrid scats were detected within the home ranges of sterilized hybrids. The other coyote/hybrid scat indicated the presence of a previously unknown individual. We suggest this method be expanded to include more of the experimental population area and be optimized for use with nuclear markers to improve detection of hybrid and back-crossed individuals. [source] | ||||||||||