August 7: Terry Fox Day (University Closed)
|Office||W371 Duff Roblin|
My research program focuses on elucidating the biology and behaviour of important forage fish species in marine ecosystems and how this shapes the biology of top predators, primarily marine birds and whales. Forage species lie at the core of complex marine food webs, providing essential linkages among trophic levels. Investigations at regional scales often reveal areas where high abundances of organisms persistently overlap during certain periods of the year, referred to as ‘biological hotspots’. There are many examples where the formation of these hotspots is driven by high-density aggregations of forage fish. Owing to the concentration of predator-prey interactions at hotspots, energy flow through marine food webs, a key ecosystem process, is maximized within these areas. This research will increase our ability to maintain the long-term productivity of this northern marine ecosystem to sustain fisheries yields and conserve marine biodiversity.
Currently, my research investigates the bio-physical mechanisms underlying the aggregation of important forage fish species and the individual energetic consequences of foraging within these areas for marine birds and whales.
I will be accepting new graduate students in May/September. STUDENTS MUST APPLY FOR SCHOLARSHIPS TO COVER ALL OR PART OF THEIR STIPEND. The University of Manitoba Graduate Fellowship (UMGF) application is typically due in February.
Check out the Davoren lab on Facebook (Davoren Lab, University of Manitoba) and follow us on Twitter and Instagram (@DavorenLab) for recent research findings and new graduate student opportunities!
Also on our Facebook page, you will find more information about current and past research projects, along with a variety of photos and videos showing our field-based and lab-based research activities.
My lab focuses on the ecology of the focal forage fish species in the northwest Atlantic, capelin (Mallotus villosus). Capelin is the primary prey for most top predators in coastal Newfoundland during the summer, including large predatory fish, marine birds and mammals. Since 2000, my lab has discovered and described deep-water (demersal) spawning sites of capelin on the exposed northeast Newfoundland coast, where this species is considered to primarily spawn on or adjacent to beaches. Capelin are thought to shift from beach to deep-water spawning habitat as temperatures at the beach become unsuitably warm later in the season. We integrate capelin tagging and sampling with long-term monitoring of spawning sites (i.e. site use, timing, and oceanographic conditions) to examine how capelin select spawning habitat. In addition, we have recently started to investigate what otolith microchemistry can tell us about the life history of capelin. Due to a northerly range expansion of capelin into arctic regions, we began collaborative research in Cumberland Sound on spawning capelin with Fisheries and Oceans Canada in 2015.
My lab has found that the persistent aggregations of demersally spawning capelin (see above) resulted in the formation of biological hotspots. We integrate ship-based surveys, with decoy experiments, whale photo-identification, and underwater video of foraging behaviour of predators at demersal spawing sites of capelin to examine the influence on these persistent prey aggregations on predator foraging behaviour. Within hotspots, we combine animal-borne activity loggers to investigate foraging behaviour of seabirds and whales in relation to hydroacoustic estimates of prey density and behaviour.
New MSc students in 2016: Julia Gulka, Laurie Maynard, Kelsey Johnson, Muriel Magnaye, Kevin Scharffenberg, Edward Jenkins, Wesley Ogloff
Carvalho Calabria P (2013-present) Coexistence of two sympatric migratory shearwaters species during their non-breeding season on the east coast of Newfoundland. PhD, Biological Sciences.
Loeppky A (2016) Otolith chemistry as a natural tag indicating natal habitat of capelin (Mallotus villosus). MSc, Biological Sciences.
McNicholl (2016) Life history of capelin Mallotus villosus and dietary overlap with Arctic Cod Boreogadus saida in the Canadian Beaufort Sea. MSc, Biological Sciences.
Crook K (2015) Investigating the impact of green sea urchin (Strongylocentrotus droebachiensis) predation on capelin eggs at deep-water spawning sites in coastal Newfoundland. MSc, Biological Sciences.
Maxner E (2014) Intrinsic and extrinsic factors influencing the timing of arrival of capelin (Mallotus villosus) to the spawning grounds. MSc, Biological Sciences.
Penton P (2013) Life history variation in capelin – a forage fish in the North Atlantic. PhD, Biological Sciences.
Sheppard K (2013) Food web dynamics in Lake Winnipeg: trophic linkages among invasive rainbow smelt and commercially important piscivorous fish. MSc, Biological Sciences (co-supervisor with Dr B Hann).
Olynyk A (2013) Food web dynamics in Lake Winnipeg: trophic linkages among zooplankton and the invasive rainbow smelt along with intraguid competition among planktivores. MSc, Biological Sciences (co-supervisor with Dr B Hann).
Elliott K (2007) Foraging behaviour of Thick-billed Murres in northern Hudson Bay. MSc, Zoology.
Harter B (2007) Black Guillemots as indicators of change in Arctic marine ecosystem. MSc, Zoology.
Penton P (2006) Demersal spawning in capelin on the northeast coast of Newfoundland. MSc, Zoology.
Undergraduate BSc Honours Students
Epp M (2016-present) Characterization of non-song vocalizations of humpback whales on their North Atlantic foraging grounds. BSc Honours.
Johnson K (2016) Variation in growth and age of sexual maturity in spawning capelin (Mallotus villosus) on the northeast Newfoundland coast. BSc Honours.
Bone B (2015) Egg cannibalism at spawning sites of capelin (Mallotus villosus) in the Northwest Atlantic. BSc Honours.
Genier G (2015) Growth rates of Arctic charr Salvenius alpinus among various stocks within the Cumberland Sound region determined by back-calculation from otoliths. BSc Honours.
Woloschiniwsky C (2014) Investigating natal philopatry in Newfoundland capelin (Mallotus villosus) using otolith elemental chemistry. BSc Honours.
Crook K (2013) Underwater foraging behaviour and search strategies of common murres (Uria aalge) and the influences of capelin (Mallotus villosus) density and antipredator behaviour. BSc Honours.
Wild K (2013) Relationships between predator density and prey density: multiple marine predator species and capelin (Mallotus villosus) in coastal Newfoundland. BSc Honours.
Sheppard K (2010) Trophic study of invasive rainbow smelt (Osmerus mordax) and native walleye (Sander vitreus) in the north basin of Lake Winnipeg, Manitoba. BSc Honours.
Olynyk A (2009) Prey selection of the invasive rainbow smelt in Lake Winnipeg. BSc Honours.
Arlt M (2007) Historical distribution of boreal caribou in the Prince Albert Greater Ecosystem in relation to landscape change. BSc Honours.
Reinfort B (2006) Biotic and abiotic factors affecting egg and pre-emergent larval mortality of capelin on a northeast Newfoundland beach. BSc Honours.
BIOL 2300 Principles of Ecology
BIOL 4220 Marine Biodiversity
BIOL 4800 Marine Field Ecology
Crook K, Maxner E, Davoren GK (2017) Temperature-based spawning habitat selection by capelin (Mallotus villosus) in Newfoundland. ICES J Mar Sci doi:10.1093/icesjms/fsx023
Crook K, Davoren GK (2016) Influence of spawning capelin (Mallotus villosus) on the density and distribution of green sea urchins (Strongylocentrotus droebachiensis) on the northeast Newfoundland coast. Mar Ecol Prog Ser 549:125-135
Maxner E, Halden NM, Roth JD, Davoren GK (2016) Intrinsic factors influence the timing of arrival of capelin (Mallotus villosus) to spawning grounds in coastal Newfoundland. Fish Res 179: 202-212
McNicholl DG, Walkusz W, Davoren GK, Reist JD (2015) Dietary characteristics of sympatric Arctic Cod and Capelin in the Canadian Arctic, Darnley Bay. Polar Biol doi:10.1007/s00300-015-1834-5
Sheppard K, Davoren GK, Hann B (2015) Diet of walleye and sauger and morphological characteristics of their prey in Lake Winnipeg. J Great Lakes Res 41: 907-915
Bairos-Novak K, Crook K, Davoren GK (2015) Relative importance of local enhancement as a search strategy for breeding seabirds: an experimental approach. Anim Behav 106: 71-78
Davoren GK, Woloschiniwsky C, Halden NM, Wang F (2015) Can otolith chemistry indicate natal habitat of capelin Mallotus villosus? J Exp Mar Biol Ecol 464: 88-95
Davoren GK, Halden NM (2014) Connectivity of capelin (Mallotus villosus) between regions and spawning habitats in Newfoundland inferred from otolith chemistry. Fish Res 159: 95-104
Penton P, McFarlane C, Spice EK, Docker M, Davoren GK (2014) Lack of genetic divergence in capelin (Mallotus villosus - Osmeridae) spawning at beach versus subtidal habitats in coastal embayments of Newfoundland. Can J Zool 92: 377–382
Crook K, Davoren GK (2014) Underwater foraging behaviour of common murres on capelin: influences of prey density and antipredator behaviour. Mar Ecol Prog Ser 501: 279–290
Davoren GK (2013) Distribution of marine predator hotspots explained by persistent areas of prey. Marine Biology 160: 3043–3058
Elliott KH, Ricklefs RE, Gaston AJ, Hatch SA, Speakman JR, Davoren GK (2013) High flight costs, but low dive costs, in auks support the biomechanical hypothesis for flightlessness in penguins. Proceedings of the National Academy of Sciences 110: 9380-9384
Harter BB, Elliott KH, Divoky GJ, Gaston AJ, Davoren GK (2013) Arctic cod (Boreogadus saida) as prey: fish length-energetics relationships in Beaufort Sea and Hudson Bay. Arctic 66: 191-196
Penton P, Davoren GK (2013) Capelin (Mallotus villosus) fecundity in post-1990s coastal Newfoundland. Marine Biology 160: 1625-1632
Penton P, Davoren GK (2013) A common garden experiment on capelin (Mallotus villosus) early life history stages to examine use of beach and deep-water spawning habitats. Journal of Experimental Marine Biology and Ecology 439: 54–60
Davoren GK (2013) Divergent use of spawning habitat by male capelin (Mallotus villosus) in a warm and cold year. Behavioural Ecology 24: 152-161
Montevecchi WA, Hedd A, McFarlane Tranquilla L, Fifield DA, Burke CM, Regular PM, Davoren GK, Garthe S, Gaston AJ, Robertson GJ, Phillips RA (2012) Tracking seabirds to identify ecologically important and high risk marine areas. Biological Conservation 156: 62-71
Davoren GK, Penton P, Burke C, Montevecchi WA (2012) Water temperature and timing of capelin spawning determine seabird diets. ICES Journal of Marine Science 69: 1234-1241
Sheppard K, Olynyk A, Davoren GK, Hann BJ (2012) Summer diet analysis of the invasive rainbow smelt (Osmerus mordax) in Lake Winnipeg, Manitoba. Journal of Great Lakes Research 38 (3): 66-71
Penton P, Davoren GK (2012) Physical characteristics of persistent deep-water spawning sites of capelin: importance for delimiting critical marine habitats. Marine Biology Research 8: 778-783
Penton P, Davoren GK, Andrews D, Montevecchi WA (2012) A comparison of egg developmental and survival rates in capelin (Mallotus villosus) on beach and demersal spawning sites in Newfoundland. Canadian Journal of Zoology 90: 248-256
Garthe S, Montevecchi WA, Davoren GK (2011) Inter-annual changes in prey fields trigger different foraging tactics in a large marine predator. Limnology and Oceanography 56: 802–812
Regular P, Davoren GK, Hedd A, Montevecchi WA (2010). Crepuscular foraging by a pursuit-diving seabird: Tactics of common murres in response to the diel vertical migration of capelin. Marine Ecology Progress Series 415: 295-304
Davoren GK, Garthe S, Montevecchi WA, Benvenuti S (2010) Influence of diel prey behaviour, prey type and whales on the foraging activities of a marine avian predator in a Low Arctic ecosystem. Marine Ecology Progress Series 404: 275–287
Gaston AJ, Bertram DF, Boyne AW, Chardine JW, Davoren GK, Diamon AW, Hedd A, Montevecchi WA, Hipfner JM, Lemon MJF, Mallory MJ, Rail J-F, Robertson GJ (2009) Changes in Canadian seabird populations and ecology since 1970 in relation to changes in oceanography and food webs. Environmental Reviews 17: 267-286
Elliott KH, Bull RD, Gaston AJ, Davoren GK (2009) Underwater and above-water search patterns of an Arctic seabird: reduced searching at small spatiotemporal scales. Behavioral Ecology and Sociobiology 63: 1773-1785
Elliott KH, Woo K, Gaston AJ, Benvenuti S, Dall’Antonia L, Davoren GK (2009) Central-place foraging in an arctic seabird provides evidence for Storer-Ashmole’s halo. Auk 126:613−625
Hedd A, Montevecchi WA, Davoren GK, Fifield DA (2009) Diets and distributions of Leach’s storm-petrel (Oceanodroma leucorhoa) before and after an ecosystem shift in the Northwest Atlantic. Canadian Journal of Zoology 87:787-801
Montevecchi WA, Benvenuti S, Garthe S, Davoren GK, Fifield D (2009) Flexible foraging tactics by a large opportunistic seabird preying on forage- and large pelagic fishes. Marine Ecology Progress Series 385: 295-306
Woo KJ, Elliott KH, Davidson M, Gaston AJ, Davoren GK (2008) Individual specialization in diet by a generalist marine predator reflects specialization in foraging behaviour. Journal of Animal Ecology 77:1082-1091
Elliott KH, Jacobs SR, Ringrose J, Gaston AJ, Davoren GK (2008) Is mass loss in Brünnich Guillemots an adaptation for improved dive performance or improve flight performance? Journal of Avian Biology 39:1-10
Elliott KH, Woo K, Gaston AJ, Benvenuti S, Dall’Antonia L, Davoren GK (2008) Seabird foraging behaviour indicates prey type. Marine Ecology Progress Series 354: 289-303
Elliott KH, Davoren GK, Gaston AJ (2008) Time allocation by a deep-diving bird reflects prey type and energy gain. Animal Behavior 75: 1301-1310
Elliott KH, Davoren GK, Gaston AJ (2008) Increasing energy expenditure for a deep-diving bird alters time allocation during the dive cycle. Animal Behavior 75: 1311-1317
Elliott KH, Gaston AJ, Davoren GK (2008) Bias in murre feeding watches. Journal of Field Ornithology 79: 298-307
Burger AE, Hitchcock CL, Stewart A, Davoren GK (2008) Coexistence and spatial distributions of Marbled Murrelets and other alcids off southwest Vancouver Island, British Columbia. Auk 125: 192-204
Penton P, Davoren GK (2008) Patterns of larval emergence of capelin (Mallotus villosus) and environmental cues at demersal spawning sites on the northeastern coast of Newfoundland. Canadian Journal of Fisheries and Aquatic Sciences 65: 1135-1143
Davoren GK, Buren A, Burke C, May C, Penton P, Record N, Rose-Taylor C, Andrews D, Reinfort B, Anderson JT, Bell T, deYoung B, Garthe S, Koen-Alonso M, Montevecchi WA (2008) An ecosystem-based research program for capelin (Mallotus villosus) in the Northwest Atlantic: overview and results. Journal of Northwest Atlantic Fishery Science 39: 35-48
Garthe S, Montevecchi WA, Davoren GK (2007) Flight destinations and foraging behaviour of northern gannets (Sula bassana) preying on a small foraging fish in a Low Arctic ecosystem. Deep-Sea Research: Part II 54: 311-320
Elliott KH, Davoren GK, Gaston AJ (2007) Influence of drag and buoyancy on dive behaviour of an arctic seabird, the thick-billed murre. Canadian Journal of Zoology 85:352-371
Davoren GK, Anderson JT, Montevecchi WA (2006) Shoal behaviour and maturity relations of spawning capelin (Mallotus villosus) off Newfoundland: demersal spawning and diel vertical movement patterns. Canadian Journal of Fisheries and Aquatic Sciences 63: 268-284
Davoren GK, Montevecchi WA (2005) Did signals from seabirds indicate changes in capelin biology during the 1990s? A reply to Carscadden (2004). Marine Ecology Progress Series 285:299-309
Burger AE, Hitchcock CL, Davoren GK (2004) Spatial aggregations of seabirds and their prey on the continental shelf off southwest Vancouver Island. Marine Ecology Progress Series 283:279-292
Davoren GK, Montevecchi WA, Anderson JT (2004) The influence of fish behaviour on search strategies of common murres Uria aalge in the Northwest Atlantic. Marine Ornithology 31:123-131
Davoren GK, Montevecchi WA, Anderson JT (2003) Search strategies of a pursuit-diving marine bird and the persistence of prey patches. Ecological Monographs 73: 463-481
Davoren GK, Montevecchi WA, Anderson JT (2003) Distribution patterns of a marine bird and its prey: habitat selection based on prey and conspecific behaviour. Marine Ecology Progress Series 256: 229-242
Davoren GK, Montevecchi WA (2003) Signals from seabirds indicate changing biology of capelin stocks. Marine Ecology Progress Series 258: 253-261
Davoren GK, Montevecchi WA (2003) Consequences of foraging trip duration on provisioning behaviour and fledging condition of common murres. Journal of Avian Biology 34: 44-53
Bertram DF, Golumbia T, Davoren GK, Harfenist A, Brown J (2003) Short visits reveal consistent patterns of interyear and intercolony variation in seabird nestling diet and performance. Canadian Journal of Zoology 80: 2190-2199
Davoren GK, Montevecchi WA, Anderson JT (2002) Scale-dependent associations of predators and prey: constraints imposed by flightlessness of common murres. Marine Ecology Progress Series 245: 259-272
Carscadden JE, Montevecchi WA, Davoren GK, Nakashima BS (2002) Trophic relationships among capelin (Mallotus villosus) and marine birds in a changing ecosystem. ICES Journal of Marine Science 59: 1027-1033
Wiese FK, Montevecchi WA, Davoren GK, Huettmann F, Diamond AW, Linke J (2001) Seabirds at risk around oil platforms in the Northwest Atlantic. Marine Pollution Bulletin 42: 1285-1290
Davoren GK (2000) Foraging variability in response to changing prey distribution in rhinoceros auklets. Marine Ecology Progress Series 198: 283-291
Davoren GK, Burger AE (1999) Differences in prey selection and behavior during self-feeding and chick provisioning in rhinoceros auklets. Animal Behavior 58: 853-863
August 7: Terry Fox Day (University Closed)
General seminar: Chenhua Li, MSc. Defense: “Improving the accuracy of stable isotope analysis in ecological studies of wildlife and helminth parasites” — Tuesday, August 1 at 10 a.m., 304 Biological Sciences.
General seminar: Dawn Pond MSc. Defense: “Floral Visitor Diversity and Efficiency in the Sub-apline Herb Polemonium brandegeei: The role of Seconday Visitors in Pollination” — Friday, August 4 at 10 a.m., 304 Biological Sciences.
General seminar: Melanie Lalonde PhD Proposal: “The New World diversification and origins of the Buckeye butterflies (genus Junonia, Nymphalidae: Nymphalini)"” — Monday, August 14 at 10 a.m., 304 Biological Sciences.
General seminar: Amanda Shave, MSc. Defense: “The impact of environmental variability and climate change on the migration and breeding phenology of a long-distance migratory songbird” — Tuesday, August 15 at 10 a.m., 304 Biological Sciences.