Using faecal DNA sampling and GIS to monitor hybridization between red wolves (Canis rufus) and coyotes (Canis latrans)

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 km(2) 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 km(2)) 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.

An Account of the Taxonomy of North American Wolves From Morphological and Genetic Analyses

“…Eleven additional historic samples (pre-1940) extended these results : eight historical samples comprised three unique sequences in the coyote clade of a parsimony analysis, and one of the three individuals in the gray wolf clade was identical to a gray wolf haplotype, but all three sequences were placed basal to Mexican wolf and western C. lupus from Alaska. Although sequence comparisons have found the mtDNA control-region haplotype of the red wolf captive population to be unique (but just two base pairs different from the nearest coyote), it falls within the divergence exhibited by coyotes and has an average divergence from coyotes of 3.24%, compared with an average of 2.79% divergence among coyote haplotypes (Adams et al 2003; Texas for evidence of hybridization. The single control-region haplotype found in the captive population of red wolves was in the coyote clade, which was strongly divergent from the wolf clade (including Mexican wolf).…”

Genetic nature of eastern wolves: Past, present and future

“…If C. lycaon is recognized as another Canis species in the Great Lakes region, current numbers of C. lupus would be overestimated, potentially influencing its conservation status. Further, in the southern USA, attempts have been made to identify and remove both hybrid C. rufus individuals with C. latrans DNA and C. latrans individuals within certain animal reserves to promote a pure genetic stock of C. rufus (see Adams et al 2003;Miller et al 2003). Such a program is likely not practical, nor desirable for eastern wolves that now comprise a continuum of morphotypes in the Great Lakes region, from larger C. lycaon animals with C. lupus genetic material in the northwest to smaller C. lycaon with C. latrans genetic material in the southeast of its current range (Grewal 2001; Figure 3).…”

Impact of climatic factors on genetic diversity of Stipa breviflora populations in Inner Mongolia

“…In rice, the combination of hierarchical cluster analysis with GIS has been demonstrated as a useful tool for the accurate visualization of the spatial distribution of existing genetic diversity within a sample of the germplasm in a given geographic area (Parsons et al, 1999). Later studies have extended the approach to other species (Adams et al, 2003;Smith et al, 2006). In this study, we examined the genetic diversity of S. breviflora populations and the role of climatic factors in explaining this diversity at 8 sites in Inner Mongolia using GIS and RAPD-based fingerprinting techniques.…”