Research Interests:

Research in the Nevitt lab focuses on the interface between sensory and behavioral ecology. The P.I., Gabrielle Nevitt, is a world-leader in avian olfaction and we are one of the few labs in the United States that studies avian olfaction in the wild. Students in the Nevitt lab study topics including foraging ecology, evolutionary traps, and ecological genetics of Procellariiform seabirds by combining field and laboratory techniques.
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Leach's Storm-Petrel (Oceanodroma leucorhoa) chick, Bon Portage Island, Nova Scotia, Canada



Study systems:

There is currently an ongoing NSF-funded project studying the major histocompatibility complex (Mhc) of Leach’s Storm-Petrels (Oceanodroma leucorhoa) on Bon Portage Island, Nova Scotia. We are interested how this cluster of genes normally linked to immune function affects the personal odor and perceived quality of individuals with differing Mhc genotypes. Results showing that birds can either detect Mhc odors or use them to choose mates would represent a paradigm shift in how biologists typically view mate choice decisions in birds. In this system, we are also interested in a variety of other questions including landscape genetics and extra-pair paternity.

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Different foraging styles of procellariiform seabirds (Nevitt 2008).
A project that recently received funding will utilize high-resolution GPS-tracking to investigate the foraging ecology of Black-browed Albatross (Thalassarche melanophrys
) nesting on the Kerguelen Islands in the Southern Indian Ocean. Work previously done there on Wandering Albatross (Diomedea exulans) has indicated that these oceanic apex predators can detect prey hot spots from at least 20km away using their acute sense of smell (Nevitt et al. 2008 PNAS, cover article). Black-browed Albatross have a different foraging style (commuter as opposed to opportunistic) than Wandering Albatross and it remains to be seen how they detect and capture prey items.


Another focus of the Nevitt Lab relates to the issue of plastic pollution in the world’s oceans. Plastics represents an anthropogenic-induced shift in the marine biosphere for which organisms need to adapt. Most major marine taxa including birds, sea turtles, marine mammals, and fish have been documented to consume marine plastic debris, mistaking it for food. We are using forensic chemistry techniques, coupled with behavioral experiments, to try and elucidate why tube-nosed seabirds consume so much plastic in the wild.







Techniques Employed:


Molecular techniques: Using PCR and sanger-based sequencing, we investigate the relationship between individual-specific odors,fitness, and genotypes in seabird colonies. We do this by isolating, amplifying, and sequencing genes of the major histocompatibility complex (MHC). MHC genes have been shown to influence individual-specific odors in other vertebrate species (Yamazaki et al. 1976, Penn 2002, Olsson et al. 2003, Milinski 2006), and are associated with immune function and adaptive selection in response to infectious diseases and pathogens (Penn and Potts, 1999). Consequently, the allelic diversity of MHC genotypes at a seabird colony may offer insights into the behavioral ecology of a population, and also illustrate adaptive responses to environmental forces affecting health and survival.


High-resolution GPS tracking allows us to remotely ask and answer questions related to foraging in procellariiform seabirds. By taking a GPS data point every 5-10 seconds (instead of a few times a day using traditional low-resolution GPS) we can infer the track a bird used to approach a prey patch (see figure to right). By examining the way a bird approaches a prey item, we can determine whether it was using primarily visual or olfactory cues to locate prey. Since many of these seabirds are of conservation concern due to bycatch from fishing vessels, how these birds locate prey is an important
forgagingapproaches.gif
Taken from Nevitt et al. 2008
problem to clarify.



To answer odor related questions we use Gas Chromatography-Mass Spectrometry (GC-MS). This methodology is often used in forensics to aid in drug detection, explosives investigation, among many other applications. We use this technique to quantify the odors emanating from bird’s feathers and soil in the bird’s burrow and relate that back to its Mhc genotype. We also plan on using this method to quantify the odors arising from marine plastic debris.


Furthermore, we use simple, but powerful behavioral bioassays to examine how birds recognize and respond to burrow, conspecific, and unknown odor cues. These choice experiments can be used on adults or chicks to address questions as diverse as can a bird recognize its burrow by scent alone or can a bird imprint on a synthetic odor in the natal environment?


Selected Publications:

Bonadonna, F., & Nevitt, G. A. (2004). Partner-specific odor recognition in an Antarctic seabird. Science, 306(5697), 835.

Cunningham, G. B., & Nevitt, G. A. (2011). Evidence for olfactory learning in procellariiform seabird chicks. Journal of Avian Biology, 42(1), 85–88.

Nevitt, G. A. (2008). Sensory ecology on the high seas: the odor world of the procellariiform seabirds. The Journal of Experimental Biology, 211, 1706–13.

Nevitt, G. A., Losekoot, M., & Weimerskirch, H. (2008). Evidence for olfactory search in wandering albatross, Diomedea exulans. Proceedings of the National Academy of Sciences of the United States of America, 105(12), 4576–81.

Nevitt, G. A., Reid, K. & Trathan, P. (2004) Testing olfactory foraging strategies in an Antarctic seabird assemblage. Journal of Experimental Biology 207, 3537-3544

Nevitt, G. A., Veit, R. R., & Kareiva, P. (1995). Dimethyl sulphide as a foraging cue for Antarctic Procellariiform seabirds. Nature, 376//, 680–682.


Current Lab Members:

Gabrielle Nevitt (P.I.)
Matthew Savoca
Brian Hoover
Sarah Jennings
Marcel Losekoot
Julie Tillman
Sukhjot Sandher