Distribution and Movement Patterns of Killer Whales ...
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Bonavista Battle Harbour L’Anse aux Meadows St. Pierre Battle Harbour Battle Harbour St. Anthony 2001……………………………… 11 August 2004………………….. 09 August 2005………………….. 14 August 2005………………….. 19 July 2006……………………… 07 September 2006………………. 26 August 2007………………….. NF0010 L’Anse aux Meadows St. Anthony Battle Harbour St. Pierre St. Pierre 09 August 2005………………….. 14 August 2005………………….. 07 September 2006………………. 21 June 2007…………………….. 30 June 2007…………………….. NF0009 L’Anse aux Meadows St. Anthony Battle Harbour Battle Harbour St. Pierre Fogo Island 09 August 2005………………….. 14 August 2005………………….. 19 July 2006……………………… 07 September 2006………………. 30 June 2007…………………….. 29 July 2007……………………… NF0007 Battle Harbour Battle Harbour Battle Harbour St. Pierre Battle Harbour Battle Harbour 11 August 2004…………………... 07 September 2004………………. 08 September 2005………………. 30 April 2006……………………. 19 July 2006……………………… 22 August 2007..…………………. NF0002 Locations sighted Dates sighted Whale ID Catalogue photograph Figure 1: Sightings of killer whales in the NW Atlantic from 1864–2008. Figure 2: Killer whales in three separate encounters off St. Pierre attacking and/or consuming (counter-clockwise from top): minke whale ( Balaenoptera acuterostrata), white-beaked dolphin (Lagenorhynchus albirostris), and unknown rorqual species. Figure 3: NW Atlantic subdivided into DFO regions. Table 1: Sighting history of four frequently-sighted killer whales. Notice the spatial and temporal range of movements, plus potential site fidelity patterns. Figure 4: Sightings distribution of identified killer whales around Newfoundland and Labrador through 2006. Figure 5: DFO researcher photographing male killer whale NF0040 in St. Anthony in 2006. Inset shows the same male photographed by DFO off St. John’s in 2008. CONCLUSIONS: Geographic Distribution: Killer whales are sighted throughout the NW Atlantic although, based on the sightings database, there are considerably more sightings in the Newfoundland and Labrador Region than in other areas of Atlantic Canada. This may represent a habitat preference for the Newfoundland and Labrador Region. Temporal Distribution: Killer whales are sighted throughout the year in Newfoundland and Labrador, including during the winter months in the presence of sea ice and breeding harp seals. Movement and Residency Patterns: Killer whales move hundreds of kilometers within a year and also exhibit site- fidelity patterns in certain areas during particular times of the year. Minke whales appear to constitute a potentially considerable portion of killer whale diet in this region. The movement and residency patterns of killer whales may be closely linked to that of their prey. ICES CM 2008/B:20 Distribution and Movement Patterns of Killer Whales (Orcinus orca) in the Northwest Atlantic Tara S. Stevens 1,2 and Jack W. Lawson 1 (1) Fisheries and Oceans Canada, NAFC, 80 East White Hills Road, St. John’s, Newfoundland and Labrador A1C 5X1, Canada (2) Memorial University of Newfoundland, Cognitive and Behavioural Ecology Program, St. John’s, Newfoundland and Labrador A1B 3X7, Canada Corresponding author e-mail: [email protected] ABSTRACT: Killer whales (Orcinus orca) occur throughout the northwest Atlantic. A sightings database and photographic catalogue, created mostly from opportunistic sources, is used to examine the occurrence of killer whales in Atlantic Canada. A majority of the sightings are from the Newfoundland and Labrador Region despite comparable observer coverage in adjacent areas such as the Gulf of St. Lawrence and Scotian Shelf, which suggests greater abundance in and habitat preference for Newfoundland and Labrador waters. Killer whales occur in all months of the year and in both near- and offshore regions, although particular sighting patterns may represent local observer effort and awareness. The distribution, movement, and residency patterns of killer whales may be closely linked to that of their prey; they have been observed harassing, attacking, and eating marine mammals, including minke whales (Balaenoptera acuterostrata), dolphins, and seals, and potentially eating fish. Some killer whales appear to remain year round in the Newfoundland and Labrador area and have been sighted during the spring within pack ice, potentially in association with breeding harp seals (Phoca groenlandica). Based on photographic records, individual killer whales in this area have been shown to move hundreds of kilometers within a year. Conversely, although there is no spatial or temporal evidence of seasonal migration, killer whales may be reliably seen in certain areas during particular times of the year, suggesting that long-term site fidelity patterns may exist within this population. METHODS: The Atlantic Canada killer whale photo-identification catalogue and sightings database were used in this study to document and analyze the distribution and movement patterns of killer whales in the NW Atlantic. The photographic catalogue is used to identify individuals while the sightings database is used to maintain all temporal, geographic, and behavioural data associated with encounters. There are over 40 contributors to the photographic catalogue and several hundred to the sightings database. RESULTS: • There are 348 sightings of killer whales in Newfoundland and Labrador, 25 in the Gulf of St. Lawrence, and 43 in the Scotian Shelf/Bay of Fundy regions. • There are 10 sightings of killer whales in the presence of ice around Newfoundland and Labrador. • There are 46 catalogued individuals in the Atlantic Canada killer whale catalogue, plus many yet unmatched photographs. • A majority of the encounters documented with photographs occurred in nearshore waters in few locations around Newfoundland and Labrador. • There are 30 foraging-related accounts, which include eight predation or attempted predation events on minke whales, three on humpback whales, possibly three on fish, and at least five scavenging-related events.
Transcript of Distribution and Movement Patterns of Killer Whales ...
BonavistaBattle HarbourL’Anse aux MeadowsSt. PierreBattle HarbourBattle HarbourSt. Anthony
2001………………………………11 August 2004…………………..09 August 2005…………………..14 August 2005…………………..19 July 2006………………………07 September 2006……………….26 August 2007…………………..
NF0010
L’Anse aux MeadowsSt. AnthonyBattle HarbourSt. PierreSt. Pierre
09 August 2005…………………..14 August 2005…………………..07 September 2006……………….21 June 2007……………………..30 June 2007……………………..
NF0009
L’Anse aux MeadowsSt. AnthonyBattle HarbourBattle HarbourSt. PierreFogo Island
09 August 2005…………………..14 August 2005…………………..19 July 2006………………………07 September 2006……………….30 June 2007……………………..29 July 2007………………………
NF0007
Battle HarbourBattle HarbourBattle HarbourSt. PierreBattle HarbourBattle Harbour
11 August 2004…………………...07 September 2004……………….08 September 2005……………….30 April 2006…………………….19 July 2006………………………22 August 2007..………………….
NF0002
Locations sightedDates sightedWhale IDCatalogue photograph
Figure 1: Sightings of killer whales in the NW Atlantic from 1864–2008.
Figure 2: Killer whales in three separate encounters off St. Pierre attacking and/or consuming(counter-clockwise from top): minke whale (Balaenoptera acuterostrata), white-beaked dolphin(Lagenorhynchus albirostris), and unknown rorqual species.
Figure 3: NW Atlantic subdivided into DFO regions.
Table 1: Sighting history of four frequently-sighted killer whales. Notice the spatial and temporal range of movements, plus potential site fidelity patterns.Figure 4: Sightings distribution of identified killer whales around Newfoundland and Labradorthrough 2006.
Figure 5: DFO researcher photographing male killer whale NF0040 in St. Anthonyin 2006. Inset shows the same male photographed by DFO off St. John’s in 2008.
CONCLUSIONS:
Geographic Distribution: Killer whales are sighted throughout the NW Atlantic although, based on the sightingsdatabase, there are considerably more sightings in the Newfoundland and Labrador Region than in other areas ofAtlantic Canada. This may represent a habitat preference for the Newfoundland and Labrador Region.
Temporal Distribution: Killer whales are sighted throughout the year in Newfoundland and Labrador, includingduring the winter months in the presence of sea ice and breeding harp seals.
Movement and Residency Patterns: Killer whales move hundreds of kilometers within a year and also exhibit site-fidelity patterns in certain areas during particular times of the year. Minke whales appear to constitute apotentially considerable portion of killer whale diet in this region. The movement and residency patterns of killerwhales may be closely linked to that of their prey.
ICES CM 2008/B:20
Distribution and Movement Patterns of Killer Whales(Orcinus orca) in the Northwest Atlantic
Tara S. Stevens1,2 and Jack W. Lawson1
(1) Fisheries and Oceans Canada, NAFC, 80 East White Hills Road, St. John’s, Newfoundland and Labrador A1C 5X1, Canada(2) Memorial University of Newfoundland, Cognitive and Behavioural Ecology Program, St. John’s, Newfoundland and Labrador A1B 3X7, Canada
Corresponding author e-mail: [email protected]
ABSTRACT:
Killer whales (Orcinus orca) occur throughout the northwest Atlantic. A sightings database and photographic catalogue, created mostly from opportunistic sources, is used to examine the occurrence of killer whales in AtlanticCanada. A majority of the sightings are from the Newfoundland and Labrador Region despite comparable observer coverage in adjacent areas such as the Gulf of St. Lawrence and Scotian Shelf, which suggests greater abundancein and habitat preference for Newfoundland and Labrador waters. Killer whales occur in all months of the year and in both near- and offshore regions, although particular sighting patterns may represent local observer effort andawareness. The distribution, movement, and residency patterns of killer whales may be closely linked to that of their prey; they have been observed harassing, attacking, and eating marine mammals, including minke whales(Balaenoptera acuterostrata), dolphins, and seals, and potentially eating fish. Some killer whales appear to remain year round in the Newfoundland and Labrador area and have been sighted during the spring within pack ice,potentially in association with breeding harp seals (Phoca groenlandica). Based on photographic records, individual killer whales in this area have been shown to move hundreds of kilometers within a year. Conversely, althoughthere is no spatial or temporal evidence of seasonal migration, killer whales may be reliably seen in certain areas during particular times of the year, suggesting that long-term site fidelity patterns may exist within this population.
METHODS:
The Atlantic Canada killer whale photo-identification catalogue and sightings database were used in this study to document and analyze thedistribution and movement patterns of killer whales in the NW Atlantic. The photographic catalogue is used to identify individuals while thesightings database is used to maintain all temporal, geographic, and behavioural data associated with encounters. There are over 40 contributorsto the photographic catalogue and several hundred to the sightings database.
RESULTS:
• There are 348 sightings of killer whales in Newfoundland and Labrador, 25 in the Gulf of St. Lawrence, and 43 in the Scotian Shelf/Bay of Fundy regions.
• There are 10 sightings of killer whales in the presence of ice around Newfoundland and Labrador.• There are 46 catalogued individuals in the Atlantic Canada killer whale catalogue, plus many yet unmatched photographs.• A majority of the encounters documented with photographs occurred in nearshore waters in few locations around Newfoundland and Labrador.• There are 30 foraging-related accounts, which include eight predation or attempted predation events on minke whales, three on humpback
whales, possibly three on fish, and at least five scavenging-related events.
