Movements and diving behaviour of mako shark in North Atlantic
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Movements and diving behaviour of mako shark in North Atlantic Gonzalo Mucientes, Nuno Queiroz, Nicholas Humphries & David Sims
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Contribution to the World Congress of Herpetology in Vancuver (August'11) by Gonzalo Mucientes, Nuno Queiroz, Nicholas Humphries & David Sims. "The shortfin mako shark (Isurus oxyrinchus) is a highly migratory, pelagic species with circum-global distribution in tropical and temperate seas. This shark is commonly found in the Atlantic Ocean and are taken as bycatch in longlining and gillnetting operations for tuna and swordfish (Xiphias gladius), activities that have expanded rapidly during the last 20 years. High demand for fins and its good-quality meat mean makos are now highly prized by fishers. But despite the high prevalence, economic importance, and vulnerability of this species, little is known about its population dynamics and habitat-use. There is some evidence from conventional tagging and fishery studies that complex population structuring and movements may be contributing to recorded declines in the western Atlantic Ocean. Shortfin mako sharks may remain faithful to particular regions, which together with males and females apparently segregating into different regions for at least part of the year may result in differential exploitation of vulnerable components of the population (e.g. mature females, juveniles) exacerbating declines. The aim of this study is to elucidate for the first time the movements and behaviour of shortfin mako sharks from satellitelinked electronic tagging and relate this to remotely sensed environmental fields to identify fine-scale habitat preferences in the Atlantic Ocean. Pop-up archival transmitting (PAT) tags were deployed, recording vertical and horizontal movements and temperature preferences of mako sharks tagged in oceanic waters. satellite tags were programmed to detach 30, 60, 90, 120 or 180 days after deployment. A total of 16 makos (8 males, 8 females) were caught and tagged in North Atlantic waters, specifically, in northwest, southwest and east of the Azores islands from 2009 – 2011. Tagged sharks ranged from 120 – 255 cm (fork length). Mako sharks displayed different movement and residency patterns, including a trans-Atlantic migration into western Iberia waters. Satellite tracked sharks also displayed deep diving behaviour into cold water, with maximum recorded depths of 1064 m (5.8 ºC) with temperature preferences ranging from 5.8 and 27ºC."
Transcript of Movements and diving behaviour of mako shark in North Atlantic
Movements and diving
behaviour of mako shark in
North Atlantic Gonzalo Mucientes, Nuno Queiroz, Nicholas Humphries & David Sims
Next amazing minutes…
• Aim
• Intro
• Methods: – Transmitters
– Tagging
• Results: – Tracks
– Diving behaviour
Aim
• The aim of this study is to elucidate for
the first time the movements and
behaviour of shortfin mako sharks from
satellite-linked electronic tagging
Intro • Short fin mako shark (Isurus oxyrinchus)
is a pelagic shark
• Lamnidae family
• Circumglobal distribution
• Highly migratory
• Ovoviviparity with oophagy
• Target by longliners (meat and fins)
Methods: Tagging
• 15 makos tagged (2009-2011)
• PATs (Mk10): 30, 60, 90, 120, 180 days (time set)
Tagging
• MAKO 86400
• Sex: Male
• FL: 125 cm
• Tagging: 24/April/2009
• Time: 30 days
• Pop-up: 24/May/2009
• Distance traveled: 1408.5 km
• 46.9 km/day
• MAKO 86399
• Sex: Male
• FL: 140 cm
• Tagging: 25/June/2010
• Time: 60 days
• Pop-up: 24/August/2010
• Distance traveled: 3118 km
• 51.1 km/day
• MAKO 86401
• Sex: Male
• FL: 220 cm
• Tagging: 30/June/2010
• Time: 90 days
• Pop-up: 28/September/2010
• Distance traveled: 5214 km
• 57.9 km/day
• MAKO 86407
• Sex: Male
• FL: 130 cm
• Tagging: 03/July/2010
• Time: 90 days
• Pop-up: 01/October/2010
• Distance traveled: 3694.5 km
• 41 km/day
• MAKO 96030
• Sex: Female
• FL: 130 cm
• Tagging: 04/July/2010
• Time: 120 days
• Pop-up: 01/November/2010
• Distance traveled: 6025.5 km
• 50.2 km/day
• MAKO 96031
• Sex: Female
• FL: 165 cm
• Tagging: 05/July/2010
• Time: 120 days
• Pop-up: 02/November/2010
• Distance traveled: 4732 km
• 39.4 km/day
• MAKO 86402
• Sex: Female
• FL: 170 cm
• Tagging: 24/April/2009
• Time: 60 days
• Pop-up: 23/June/2009
• Distance traveled: 5168.5 km
• 86.1 km/day
• MAKO 86408
• Sex: Male
• FL: 180 cm
• Tagging: 27/June/2010
• Time: 120 days
• Pop-up: 25/October/2010
• Distance traveled: 5699 km
• 47.5 km/day
• MAKO 107089
• Sex: Female
• FL: 220 cm
• Tagging: 21/August/2011
• Time: 120 days
• Pop-up: 19/December/2011
• Distance traveled: 5160 km
• 43 km/day
• MAKO 107092
• Sex: Male
• FL: 170 cm
• Tagging: 03/September/2011
• Time: 120 days
• Pop-up: 01/January/2012
• Distance traveled: 2414.5 km
• 20.1 km/day
• MAKO 107091 (I. paucus)
• Sex: Female
• FL: 245 cm
• Tagging: 30/August/2011
• Time: 120 days
• Pop-up: 28/December/2011
• Distance traveled: 3105.5 km
• 25.9 km/day
• MAKO 107090
• Sex: Male
• FL: 255 cm
• Tagging: 22/August/2011
• Time: 120 days
• Pop-up: 20/December/2011
• Distance traveled: 5933 km
• 49.4 km/day
Results
125 130 130 140
165 170 170 170 170 180
220 220
240 245 255
0
50
100
150
200
250
300
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
7 8
Male Female
1
2 2
7
3
0
1
2
3
4
5
6
7
30 60 90 120 180
6 6
Sex Days
Length
Horizontal movements • Two main behaviours (selected tracks)
Feeding area Migration
Mako 86407
• Sex: Male
• FL: 180 cm
• Tagging: 27/June/2010
• Time: 120 days
• Pop-up: 25/October/2010
• Distance traveled: 5699 km
• Ratio 47.5 km/day
Mako 86408
• Sex: Male
• FL: 130 cm
• Tagging: 03/July/2010
• Time: 90 days
• Pop-up: 01/October/2010
• Distance traveled: 3700 km
• Ratio 41.1 km/day
Mako 86402
• Sex: Female • FL: 170 cm • Tagging: 24/abril/2009 • Time: 60 days
• Pop-up: 23/junio/2009 • Distance: 5168.5 km • Ratio: 86.2 km/day
• Sex: Female
• FL: 220 cm
• Tagging: 21/August/2011
• Time: 120 days
• Pop-up: 19/December/2011
• Distance traveled: 5160 km
• 43 km/day
Mako 107089
Mako 96030 • Sex: Female
• FL: 130 cm
• Tagging: 04/July/2010
• Time: 120 days
• Pop-up: 01/November/2010
• Distance traveled: 6025.5 km
• Ratio: 50.2 km/day
All tracks
Kernel density
Diving behaviour
• Depth
• Temperature (Thermocline)
• Time
Mako 86407
•Sex: Male •Tagging: 03/July/2010 •Time: 90 days
•Pop-up: 01/October/2010 •FL: 130 cm •Distance: 3700 km •Ratio: 41.11 km/day
Mako 86408
• Sex: Male
• FL: 180 cm
• Tagging: 27/June/2010
• Time: 120 days
• Pop-up: 25/October/2010
• Distance traveled: 5699 km
• 47.5 km/day
0
10
20
30
0 200 400 600
MinTemp1
MaxTemp1
Mako 107090
• Sex: Male
• FL: 255 cm
• Tagging: 22/August/2011
• Time: 120 days
• Pop-up: 20/December/2011
• Distance traveled: 5933 km
• 49.4 km/day
Mako 107089
• Sex: Female
• FL: 220 cm
• Tagging: 21/August/2011
• Time: 120 days
• Pop-up: 19/December/2011
• Distance traveled: 5160 km
• 43 km/day
Diving behaviour - Length
• MAKO 107090
• Sex: Male
• FL: 255 cm • Tagging: 22/August/2011
• Time: 120 days
• Pop-up: 20/December/2011
• Distance traveled: 5933 km
• 49.4 km/day
• MAKO 107092
• Sex: Male
• FL: 170 cm • Tagging: 03/September/2011
• Time: 120 days
• Pop-up: 01/January/2012
• Distance traveled: 2414.5 km
• 20.1 km/day
In general…
Temperature
Preys distribution
Thermocline
Diving behavoiur of
sharks
Conclusions
• Mako sharks displayed different movement and
residency patterns, including a trans-Atlantic migration
into western Iberia waters.
• Sharks also displayed deep diving behaviour into cold
water, with maximum recorded depths of 1744 m (I.
paucus) and 1480 (I. oxyrinchus), although most do not
exceed 600 m
• Temperature preferences ranging from 5.8 and 27ºC.
• Different behaviour between adult and juvenile makos.
Thanks
for your
attention!!
Contact:
This work was supported by FCT
(Fundação para a Ciência e a Tecnologia) and the Save our Seas
Foundation
