Top predators and Ocean interaction in Southern
Oceans and archipelago islands
Azwianewi Makhado,
M. Seakamela, N. de Bruyn, P. Ryan, P. Pistorius & R. Crawford
Oceans and Coasts
Marion-centred
view of the
world
Antarctic
Circumpolar
Current
Prince
Edward
Islands
1. Because we
are obliged to do
so
2. Unique research
opportunities
3. Climate
change
4. Conservation
5. Student
training
Research at the PEIs
1. To assess and monitor population sizes, trends and conservation status of Top predators at the
Prince Edward Islands. – Population ecology and conservation
2. To understand key driver of poor conservation status of some species at the Prince Edward Islands
and advise remedial measures - Species assessment and management
3. To assess the usefulness of different indices as indicators of environmental change in Southern
Ocean ecosystems – Climate change
4. To contribute to CCAMLR’s and ACAP - International engagements
5. To build on capacity within the southern ocean region - Training
Temperature trends
in the sub-Antarctic
region
Sub-Antarctic among the fastest warming regions.
Since 1960, rainfall has decreased 40% and temperature
has warmed 0.21oC per decade
Many marine top predators
have a poor and deteriorating
conservation status
e.g. seabirds
1984
2014
1.
2.
3.
4.
5.
VU
LC
CR
EN
VU
NT
LC
CR- critically endangered
En- endangered
VU- vulnerable
NT- near threatened
LC- least concern
28 species of seabird breed at the Prince Edward Islands; 16
on the surface, 12 in burrows. The table shows the
contribution of the Prince Edward Islands to the world
populations of the 16 surface-nesting species
40% of all
Wandering
Albatrosses
(Vulnerable)
24% of all
Sooty
Albatrosses and 33
% Crozet shag
(Endangered)
Monitor the
health of the
Southern Ocean
by tracking top
predator:
• population
size
• body
condition
• reproduction
• growth rates
• diet
• pollutants
Trends in numbers shows that the conservation status of
some species at the Island are of conservation concern
2000
3000
2500
1500
2000
1000
1500
Wandering albatross
500
1000
Southern giant petrel
500
0
1980
1985
1990
1995
2000
Sooty albatross
2005
0
1980
2010
Light Mantled albatross
1985
1600
1400
1200
1000
800
600
400
200
0
1990
1995
2000
King penguin
2005
2010
Crested penguins
Numbers of both species of crested penguin breeding at Marion Island have
decreased – the Southern Rockhopper Penguin is regionally Endangered; the
Macaroni Penguin is Vulnerable
Southern Rockhopper Penguin
2012/13
2010/11
2008/09
2006/07
2004/05
2002/03
2012/13
2010/11
2008/09
2006/07
2004/05
2002/03
2000/01
1998/99
1996/97
250
2000/01
300
1998/99
350
1996/97
400
200
160
120
80
40
0
1994/95
Thousand pairs
450
1994/95
Thousand pairs
Macaroni Penguin
Predators may indicate change in ecosystems where
lower trophic levels are not monitored and assist in
Island ecosystem interaction i.e. nutrient cycles
Gentoo Penguin
Crozet Shag
2012/13
2010/11
2008/09
2006/07
2004/05
2002/03
2000/01
1998/99
1996/97
1400
1200
1000
800
600
400
200
0
1994/95
Pairs
E.g. numbers of Crozet Shags and Gentoo Penguins breeding at Marion Island have
shown decreasing trends – both are benthic feeders eating similar prey. The
congruent trends suggest possible ongoing change in the benthic marine
environment. Regionally the Crozet Shag is Critically Endangered and the Gentoo
Penguin is Endangered
Scaled number of females
Southern elephant seal populations: one of the
longest tagging seals in the world
1.0
0.8
0.6
Macquarie Island
Fitted SE
0.4
Marion Island
Fitted SE
0.2
0.0
1988
1990
1992
1994
1996
1998
Census year
2000
2002
2004
www.marionseals.com
4. Climate
change
Sub-Antarctic among the fastest warming regions.
Since 1960, rainfall has decreased 40% and temperature has
warmed 0.21oC per decade
Seals dived to deeper depths when foraging in warmer waters.
Both male and female seals spent less time at targeted dive depths in warmer water, and were
presumably less successful foragers when diving in warmer water.
Continued warming of the Southern Ocean may result in the distribution of prey for southern
elephant seals shifting either poleward and/or to increasing depths, presumably increasing
energy utilization while searching for prey.
Fur seals
Assessment of foraging success and population trends
a. Attendance patterns
b. Population growth
c. Pup growth
d. Foraging
Overwintering distributions of crested penguins in the
South Indian Ocean (collaboration with France)
Macaroni (red and pink lines), Southern Rockhopper (yellow and white) and Northern
Rockhopper (green) Penguins. Locations: Marion (circle), Crozet (triangle), Kerguelen
(lozenge) and Amsterdam (square) islands. Macaroni and Southern Rockhopper
Penguins at island groups have different winter feeding grounds
Partitioning of foraging grounds of yellow-nosed
albatrosses
Spatial management of oceans expected to play an
important role in biodiversity conservation
The Prince Edward Islands Marine
Protected Area was proclaimed in April
2013
Controlled zone light grey; restricted zones dark grey
New challenges and Opportunities
Land-breeding marine predators as bio-indicators of change in
western Dronning Maud Land, Antarctica
• Circumpolar Comparative study on the breeding ecology and foraging
behavior of some seabirds species breeding in SO i.e Skua etc.
• Population structure and contemporary gene flow in two sympatricallybreeding Southern Ocean predators with contrasting demographics
• Interactive effects of multiple stressors and environmental change on
marine predators across the Antarctic Polar Front
• Seals from Space: satellite-based censuses of pack-ice seals in Dronning
Maud Land, Antarctica
DISTRIBUTION AND ABUNDANCE OF HUMPBACK WHALES OFF
COAST OF SOUTH AFRICA
Interesting Observations
Eradication is
feasible
1. Because we
are obliged to do
so
2. Unique research
opportunities
3. Climate
change
4. Conservation
5. Student
training
THANK YOU