(1) Genomic consequences of hybridization for mainland and island endemic monochromatic species that have independently come into secondary contact with a dichromatic sister species, the mallard (Anas platyrhynchos). Specifically, I aim to determine the genetic consequence of gene flow by sampling the genomes and estimating hybridization rates of several Island and mainland species that includes Hawaiian ducks, New Zealand grey ducks, American Black ducks, and mottled ducks. The data will be used to understand the influence of gene flow at evolutionary scales and as a means to prioritize conservation goals.
(a) Ancient DNA and full genome resequencing of Hawaiian ducks, Laysan ducks, and mallards to understand the genome of a potential hybrid species:
(2) Genetic and morphological associations between dichromatic and monochromatic species, and in relevance to the evolution of dichromatism. First, I aim to identify and genetically vet hybrid phenotypic characters through genome wide association studies (GWAS) that will undoubtedly help species’ recovery programs. Next, I will use the pair-wise monochromatic-mallard comparisons to understand the genetic (with a focus on the Z sex chromosome) and hormonal importance for the evolution of dichromatism in this group, and as compared to other groups.
(3) Movement ecology and population genetics of the Mexican duck: For Mexican ducks, I plan to undertake additional scientific sampling trips in regions that I previously was unable to access full body specimens: Chihuahua and Southwestern USA (all samples will be deposited at the UTEP biodiversity collections). Finally, we will be starting a long term monitoring program of Mexican ducks around the greater El Paso region and Southern New Mexico. I will use various sampling techniques to determine population structure (e.g., genetic monitoring), movement behavior (e.g., band-recovery data, telemetry), and how Mexican ducks may act as a reservoir of Avian Influenza (AI) in the region (e.g., cloacal swabs + PCR, ELISA).
(3A) Behavioral & Breeding Ecology of Mexican ducks: We seek to fill in large gaps in knowledge regarding basic ecology of Mexican ducks. First, we will try to understand habitat requirments for successful nesting and brood survival. Next, we will be conducting time budget analyses to determine how Mexican ducks partition their time across various daily routines (e.g., resting, feeding, preening, mate searching, etc.).
Undergraduate Student Esmeralda Duenez Searching for Mexican duck nests (left) & our first Mexican duck nest (right)!
(4) Genomics of New Zealand Grey ducks and intensity of hybridization with mallards. 95% of New Zealand grey ducks (Anas superciliosa) are believed to be genetically extinct due to wide-spread hybridization with introduced mallards (A. platyrhynchos). Here, we use next-generation sequencing on samples across the species’ geographical distributions to answer questions regarding population structure and extent of hybridization between mallards and New Zealand grey ducks. We aim to answer whether any NZ grey ducks exist in the wild or are now only relics within a hybrid swarm. See the video of us in New Zealand made by NZ Fish and Game for more info: https://www.facebook.com/FishandGameNZ/videos/1998571646881392/
(5) Population Genetics of a feral x wild mallard hybrid swarm. Release of domestic stock conspecifics into the wild is a practice used world-wide to augment various wildlife populations. Where these releases are common and intensive, concern for wild populations have increased because breeding with released or feral conspecifics can cause a decrease in genetic variation, leading to a loss of adaptation and overall fitness within the wild population. Since the early 1900’s, government agencies and private citizens have raised and released game-farm mallards to augment wild populations. Up until the 1960s, up to 500,000 game-farm mallards were released annually in the United States. Today, game-farm mallard releases are less than historic numbers, but approximately 275,000 game-farm mallards continued to be released annually by private citizens in the US. Published work by Lavretsky and colleagues (see Publications) has established that the release of these domesticated mallards has resulted in a feral x wild mallard hybrid swarm in eastern North America. My lab is employing partial and full genome re-sequencing on hundreds of samples to fully comprehend the contribution of game-farm mallards to the genetic composition of North America mallards, and to what extent game-farm mallards and associated phenotypes are causing maladaptation in wild mallards through introgression : https://www.utep.edu/newsfeed/