Effects of fine-scale oceanographic features on the distribution and movements of harbour porpoises Phocoena phocoena in the Bay of Fundy

We describe an integrative approach to studying the fine-scale distribution of harbour porpoises Phocoena phocoena in the Bay of Fundy, using satellite telemetry, line transect surveys and remote sensing techniques. Analysis of satellite telemetry data from 6 porpoises (5 male, 1 female) revealed that over the course of a month individuals ranged across large areas (7738 to 11 289 km 2 ) but concentrated their movements in small focal regions (August mean = 294 km 2 , September mean = 252 km 2 ), often proximate to islands, headlands, or restricted channels. Line transect surveys (n = 25 flood tide, n = 20 ebb tide) in the focal region of 2 tagged animals revealed that relative porpoise density (animals km -2 ) was significantly greater during flood (9.59) than ebb tide phases (1.79). Hydro-acoustic prey surveys revealed aggregations of prey along localized fronts in this region. Remote sensing images indicated the presence of an island wake in the focal region during flood tides, providing an ecological context for our observations of high densities of porpoises. Remote sensing revealed the existence of a headland wake in the focal region of another porpoise near Cam- pobello Island. These results support the hypothesis that regions of enhanced relative vorticity, like island and headland wakes, aggregate prey and represent important foraging habitat for harbour porpoises in the Bay of Fundy.

[1]  Paul M. Thompson,et al.  Functional mechanisms underlying cetacean distribution patterns: hotspots for bottlenose dolphins are linked to foraging , 2004 .

[2]  B. Mate,et al.  North Atlantic right whale habitat in the lower Bay of Fundy and on the SW Scotian Shelf during 1999–2001 , 2003 .

[3]  Deborah Austin,et al.  A THREE‐STAGE ALGORITHM FOR FILTERING ERRONEOUS ARGOS SATELLITE LOCATIONS , 2003 .

[4]  W. Au,et al.  Prey dynamics affect foraging by a pelagic predator (Stenella longirostris) over a range of spatial and temporal scales , 2003, Behavioral Ecology and Sociobiology.

[5]  Torkild Tveraa,et al.  USING FIRST‐PASSAGE TIME IN THE ANALYSIS OF AREA‐RESTRICTED SEARCH AND HABITAT SELECTION , 2003 .

[6]  J. Lu,et al.  Marine oil spill detection, statistics and mapping with ERS SAR imagery in south-east Asia , 2003 .

[7]  Robert A. Ronconi,et al.  Management options to reduce boat disturbance on foraging black guillemots (Cepphus grylle) in the Bay of Fundy , 2002 .

[8]  D. Johnston,et al.  The effect of acoustic harassment devices on harbour porpoises (Phocoena phocoena) in the Bay of Fundy, Canada , 2002 .

[9]  W. Turrell,et al.  Influence of the tidal cycle and a tidal intrusion front on the spatio-temporal distribution of coastal bottlenose dolphins , 2002 .

[10]  Peter Coutis,et al.  The physical and biological impact of a small island wake in the deep ocean , 2002 .

[11]  K. Hyrenbach,et al.  Oceanographic habitats of two sympatric North Pacific albatrosses during the breeding season , 2002 .

[12]  R. Dietz,et al.  Autumn movements, home ranges, and winter density of narwhals (Monodon monoceros) tagged in Tremblay Sound, Baffin Island , 2002, Polar Biology.

[13]  Peter I. Miller,et al.  Sea-surface signatures of the island mass effect phenomena around Madeira Island, Northeast Atlantic , 2002 .

[14]  David L. Borchers,et al.  Abundance of harbour porpoise and other cetaceans in the North Sea and adjacent waters , 2002 .

[15]  R. W. Baird,et al.  Fluctuations in distribution and patterns of individual range use of northern bottlenose whales , 2002 .

[16]  Jeannette E. Zamon Seal predation on salmon and forage fish schools as a function of tidal currents in the San Juan Islands, Washington, USA , 2001 .

[17]  K. Hyrenbach,et al.  POST-BREEDING MOVEMENTS OF A MALE BLACK-FOOTED ALBATROSS PHOEBASTRIA NIGRIPES , 2001 .

[18]  D. Palka,et al.  Accounting for responsive movement in line transect estimates of abundance , 2001 .

[19]  A. Read Trends in the maternal investment of harbour porpoises are uncoupled from the dynamics of their primary prey , 2001, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[20]  D. Sims,et al.  Annual social behaviour of basking sharks associated with coastal front areas , 2000, Proceedings of the Royal Society of London. Series B: Biological Sciences.

[21]  Panayiotis Diplas,et al.  Using two-dimensional hydrodynamic models at scales of ecological importance , 2000 .

[22]  D. Kobayashi,et al.  Turtles on the edge: movement of loggerhead turtles (Caretta caretta) along oceanic fronts, spanning longline fishing grounds in the central North Pacific, 1997–1998 , 2000 .

[23]  John Calambokidis,et al.  MOVEMENTS OF NORTH PACIFIC BLUE WHALES DURING THE FEEDING SEASON OFF SOUTHERN CALIFORNIA AND THEIR SOUTHERN FALL MIGRATION1 , 1999 .

[24]  R. Bonduriansky,et al.  Eliminating autocorrelation reduces biological relevance of home range estimates , 1999 .

[25]  D. Sims,et al.  Selective foraging behaviour of basking sharks on zooplankton in a small-scale front , 1998, Nature.

[26]  H. Koopman Topographical Distribution of the Blubber of Harbor Porpoises (Phocoena phocoena) , 1998 .

[27]  Andrew J. Read,et al.  Monitoring the movements of harbour porpoises (Phocoena phocoena) with satellite telemetry , 1997 .

[28]  George L. Hunt,et al.  Foraging ecology of short-tailed shearwaters near the Pribilof Islands, Bering Sea , 1996 .

[29]  R. Powell,et al.  An Evaluation of the Accuracy of Kernel Density Estimators for Home Range Analysis , 1996 .

[30]  G. Hunt,et al.  Foraging by murres (Uria spp.) at tidal fronts surrounding the Pribilof Islands, Alaska, USA , 1996 .

[31]  Mark V. Trevorrow,et al.  Three-dimensional structure in a tidal convergence front , 1995 .

[32]  David R. Anderson,et al.  Distance Sampling: Estimating Abundance of Biological Populations , 1995 .

[33]  Brent S. Stewart,et al.  Double Migrations of the Northern Elephant Seal, Mirounga angustirostris , 1995 .

[34]  L. Mullineaux,et al.  Transport of juvenile gem clams (Gemma gemma) in headland wake , 1994 .

[35]  P. Harrison,et al.  Tidal wake-mixing localized effects on primary production and zooplankton distributions in the Strait of Georgia, British Columbia , 1992 .

[36]  J. Font,et al.  Sea surface mesoscale structures imaged by the synthetic aperture radar , 1992 .

[37]  Bernie J. McConnell,et al.  Foraging ecology of southern elephant seals in relation to the bathymetry and productivity of the Southern Ocean , 1992, Antarctic Science.

[38]  K. Mann,et al.  Dynamics of marine ecosystems:biological-physical interactions in the oceans , 1992 .

[39]  A. Read,et al.  Consumption of euphausiids by harbour porpoise (Phocoena phocoena) calves in the Bay of Fundy , 1992 .

[40]  S. Ekstrand Landsat TM based quantification of chlorophyll-a during algae blooms in coastal waters , 1992 .

[41]  S. Pond,et al.  Tidal plume generation around a promontory: effects on nutrient concentrations and primary productivity , 1992 .

[42]  R. Signell,et al.  Transient eddy formation around headlands , 1991 .

[43]  Timothy D. Reynolds,et al.  Time intervals for estimating pronghorn and coyote home ranges and daily movements , 1990 .

[44]  C. Recchia,et al.  Stomach contents of harbour porpoises, Phocoena phocoena (L.), from the Bay of Fundy , 1989 .

[45]  B. Worton Kernel methods for estimating the utilization distribution in home-range studies , 1989 .

[46]  W. Hamner,et al.  Topographically Controlled Fronts in the Ocean and Their Biological Influence , 1988, Science.

[47]  P. M. Payne,et al.  The distribution of white-sided (Lagenorhynchus acutus) and common dolphins (Delphinus delphis) vs. environmental features of the continental shelf of the northeastern United States , 1988 .

[48]  Helene Lair,et al.  Estimating the Location of the Focal Center in Red Squirrel Home Ranges , 1987 .

[49]  G. Odell,et al.  Swarms of Predators Exhibit "Preytaxis" if Individual Predators Use Area-Restricted Search , 1987, The American Naturalist.

[50]  R. Kenney,et al.  Cetacean high-use habitats of the northeast United States continental shelf , 1986 .

[51]  S. Spencer,et al.  Assessment of space-use patterns in the hispid cotton rat (Sigmodon hispidus) , 1985, Oecologia.

[52]  D. E. Gaskin,et al.  Habitat Index Analysis of the Harbor Porpoise (Phocoena phocoena) in the Southern Coastal Bay of Fundy, Canada , 1985 .

[53]  D. Jupp,et al.  River plumes, Coral Reefs and mixing in the Gulf of Papua and the northern Great Barrier Reef , 1984 .

[54]  D. E. Gaskin,et al.  Predicting the Movements of Juvenile Atlantic Herring (Clupea harengus harengus) in the SW Bay of Fundy Using Computer Simulation Techniques , 1983 .

[55]  R. W. Sheldon,et al.  Population densities of euphausiids off Nova Scotia as indicated by net samples, whale stomach contents, and sonar , 1978 .

[56]  P. Taylor,et al.  Test of optimal sampling by foraging great tits , 1978 .

[57]  E. Charnov Optimal foraging, the marginal value theorem. , 1976, Theoretical population biology.

[58]  D. E. Gaskin,et al.  The diet of harbor porpoises (Phocoena phocoena (L.)) in coastal waters of eastern Canada, with special reference to the Bay of Fundy. , 1974, Canadian journal of zoology.

[59]  R. Macarthur,et al.  On Optimal Use of a Patchy Environment , 1966, The American Naturalist.

[60]  M. Doty,et al.  The Island Mass Effect , 1956 .

[61]  W. H. Burt Territoriality and Home Range Concepts as Applied to Mammals , 1943 .

[62]  E. Slooten,et al.  Small-boat surveys for coastal dolphins: line-transect surveys for Hector's dolphins (Cephalorhynchus hectori) , 2004 .

[63]  Gary D. Melvin,et al.  Extraction and comparison of acoustic backscatter from a calibrated multi- and single-beam sonar , 2003 .

[64]  Bruce E. Lyon,et al.  Individual variation in prey selection by sea otters: patterns, causes and implications , 2003 .

[65]  W. Wolff,et al.  Responses of seabirds, in particular prions (Pachyptila sp.), to small-scale processes in the Antarctic Polar Front , 2002 .

[66]  D. Kobayashi,et al.  The transition zone chlorophyll front, a dynamic global feature defining migration and forage habitat for marine resources , 2001 .

[67]  Wei Li,et al.  Spectral Signatures of Coral Reefs: Features from Space , 2001 .

[68]  R. Leben,et al.  Ship and Satellite Studies of Mesoscale Circulation and Sperm Whale Habitats in the Northeast Gulf of Mexico During GulfCet II , 2000 .

[69]  Robert B. Griffin,et al.  SPERM WHALE DISTRIBUTIONS AND COMMUNITY ECOLOGY ASSOCIATED WITH A WARM‐CORE RING OFF GEORGES BANK , 1999 .

[70]  Andrew J. Read,et al.  Applications of new technology to the conservation of porpoises , 1998 .

[71]  Eric D. Barton,et al.  The influence of island-generated eddies on chlorophyll distribution : a study of mesoscale variation around Gran Canaria , 1997 .

[72]  P. R. Wiepkema,et al.  The harbour porpoise (Phocoena phocoena) , 1997 .

[73]  P. Berggren Stocks, status and survival of harbour porpoises (phocoena phocoena) in Swedish waters , 1995 .

[74]  Peter Calow,et al.  Physiological ecology of animals , 1986 .

[75]  W. Hamner,et al.  Recurring aggregation of Zooplankton by a tidal current , 1980 .

[76]  N. Tinbergen,et al.  An Experiment On Spacing-Out as a Defence Against Predation , 1967 .