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Animals of the PolesAnimals of the Poles
Presented by Kate DevlinPresented by Kate Devlin
Antarctic krill, Euphausia superba; Actual Size: 58 mm long (Photo by Uwe Kils) http://www.ecoscope.com/krill/index.htm
Photo: Alastair Rae
Arctic Tern, Sterna paradisaea
Photo: Carsten Egevang and Iain Stenhouse
Arctic Tern and the midnight sun….Greenland
Arctic Tern Breeding Range in Red, Non-Breeding locations in blue, Migration routes in green
Notice anything curious about this map?Map by A.Trepte
Map by A.Trepte
Long distance trip between ~late-July and October by an Arctic Tern banded as chick
Direct flight = ~6165 miles
Photos: Carsten Egevang and Iain Stenhouse
50 data loggers in 2007, to be recaptured in 2008
Gulf of Maine
Maine
New Brunswick
Nova Scotia
100 km
Collaborative Project
www.ngdc.noaa.gov/mgg/shorelines
USFWS
Petit Manan Island
Devlin
Machias Seal Island
Seal Island
USFWS
Matinicus Rock
© 2001 P. W. Hirtle
Year
1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000
Num
ber
of N
estin
g P
airs
of
Ter
ns
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000Arctic TernCommon TernRoseate Tern
Nesting Pairs of Terns between southern Maine and Grand Manan
Year
1984 1986 1988 1990 1992 1994 1996 1998 2000 2002 2004
Num
ber
of N
estin
g P
airs
of
Ter
ns
0
1000
2000
3000
4000
5000
6000
7000
8000
9000
10000Arctic TernCommon TernArctic Terns on 4 Islands
Nesting Pairs of Terns between southern Maine and Grand Manan
Allard
Diamond
Photos: Carsten Egevang, Iain Stenhouse, Karel Allard, Antony Diamond
Field work – small islands, many hours in bird blinds spent watching what happens – eggs hatching, chicks growing, adults bringing in food, etc.
Photos: USFWS and Paul Cranford
Puffins and Terns
Cranford
Cranford
USFWS
USFWS
USFWS
“Relative” tameness of study species….yes, it did fly away…
Devlin
Polar Bear, Ursus maritimus
www.free-picture-graphic.org.uk
For Text interview: http://thirdcoastfestival.org/behind_scenes_bryant.asp
For Audio: http://audio.wbez.org/thirdcoast/player/3player_new.asp?fileId=prey
A color-marked and banded Sabine’s Gull, Larus sabini
Seabird Research
Photo: Carsten Egevang, and Iain Stenhouse
Photo by Alastair Rae
Photos: Carsten Egevang and Iain Stenhouse
Sabine’s Gull: trapping, calling and one day old chick
Sunlight over drifting Canadian ice floes
Photo by Paul Nicklen
http://science.nationalgeographic.com/science/photos/tundra-wildlife-plants.html
http://www.huntingsociety.org/PolarBearpics.html
Polar Bear on ice…
http://www.arcticartsales.com/polarbear_skull.html
http://www.arcticartsales.com/polarbear_skull.html
http://www.arcticartsales.com/polarbear_skull.html
Photo: Alastair Rae
Photo by: Captain Budd Christman, NOAA Corps
http://www.getfreephotos.com
Foraging caribou herdPhotograph by Joel Sartore
Caribou herd on Arctic tundraPhotograph by Norbert Rosing
http://science.nationalgeographic.com/science/photos/tundra-wildlife-plants.html
http://www.getfreephotos.com
http://www.getfreephotos.com
http://www.getfreephotos.com
http://www.getfreephotos.com
Photos: Carsten Egevang, and Iain Stenhouse
http://www.polarbearsinternational.org/lessons-for-your-classroom/polar-bears-and-ecotourism/
http://www.huntingsociety.org/PolarBearpics.html
Polar bear crossing pack icePhoto by Ralph Lee Hopkins
http://science.nationalgeographic.com/science/photos/tundra-wildlife-plants.html
Allard
Allard
Jamieson
East Bay
Nuuk
Nanortalik
Satellite Tracking of Eider Ducks is a joint venture by researchers in Greenland and Canada
http://eastbay_eiders.trackit.cubitech.dk/main
Photo: Alastair RaeDovekie, Alle alle
“A number of bird species, including several globally endangered seabird species, are projected to lose more than 50% of their breeding area during this century.”
“Many species from around the world depend on summer breeding and feeding grounds in the Arctic, and climate change will alter some of these habitats significantly.”
Source: Arctic Climate Impact Assessment (ACIA) 2004
Photo: Alastair Rae
http://www.atanarjuat.com/media/press.php
Photo by: Giuseppe ZibordiCredit: Michael Van Woert, NOAA NESDIS, ORA
http://sciencebulletins.amnh.org/?sid=b.s.antarctica_life.20071210&src=e
Food Webs and Species Interactions
• Community Webs– A food web summarizes the feeding relations in a
community.– Complexity and Structure
• Keystone Species– The feeding activities of a few keystone species may
control the structure of communities– Effects on Diversity
Winemiller 1990 in Molles 2007; Fig 17.3
Winemiller 1990 in Molles 2007; Fig 17.3
Strong Interactions and Food Web Structure
Robert Paine (1966, 1969)
– Suggested criterion for strong interaction is degree of influence on community structure.
– Not based on quantity of energy flow, but on degree of influence
Paine suggested feeding activities of a few species may have a dominant influence on community structure.
– He predicted that some predators may increase diversity
• Keep prey populations below carrying capacity– Number of individuals that environment can
sustain long term
• Reduces potential for competitive exclusion between prey species
– Depends upon niche overlap; lower pop. size means less intense overlap
• Reduced competitive exclusion means more species can coexist
From Molles 2007, Fig.
17.6
Keystone Species
Pisaster ochraceus
Nucella lamellosa or Thais lamellosa
PREDATORS
Mytilus californianus
Lepidochiton flectens Patella vulgata
Balanus glandula
PREY SPECIES
Keystone Species
From Molles 2007, Fig.
17.6
© Paul Foretic http://baja.divebums.com/FieldID/Pages/sun_star_gulf.html
Food Web Structure and Species Diversity
• Paine found as number of species in intertidal food webs increased, proportion of the web represented by predators also increased.
– According to his hypothesis, higher proportion of predators produces higher predation pressure on prey populations, in turn promoting higher diversity.
• Removal of starfish (top predator) caused decline in diversity from 15 to 8 species
• After 3 months
– Barnacle (Balanus glandula) took over 60-80 % of space
• After 1 year, 2 species dominate – this lasted for 5 years– Mussels and goose-neck barnacles
– Other species – no attachment points
• Space was a limiting resource
• Pisaster = keystone species
Consumers’ Effects on Local Diversity
• Jane Lubchenko (1978) proposed to resolve the effect herbivores have on plant diversity,
– Herbivore food preference.
– Competitive relationships between plant species in the local community.
– Variance in feeding preferences and competitive relationships across environments.
Consumers’ Effects on Local Diversity
• Lubchenko studied influence of intertidal snail (Littorina littorea) on structure of an algal community.
– Snails fed on green (Enteromorpha spp.) and red (Chondrus crispus) algae.
• Under normal conditions, Enteromorpha out-competes Chondrus in tide pools, and Littornia prefers Enteromorpha.
– In the absence of snails, Chondrus is competitively displaced.
Littorina littorea Enteromorpha spp.
Chondrus crispus
Consumers’ Effects on Local Diversity
Molles 2007, Fig. 17.8
Consumers’ Effects on Local Diversity
• When snails are present in high densities, Littorina grazes down Enteromorpha, releasing Chondrus from competition.
– Green crabs (Carcinus maenus) prey on young snails, preventing juveniles from colonizing tide pools.
– Populations of Carcinus are controlled by seagulls.
J. AndersonJ. Anderson
Consumers’ Effects on Local Diversity
– Low snail density - Enteromorpha dominates tide pool.
– Medium snail density - Competitive exclusion eliminated, and algal diversity increased.
– High snail density - Feeding requirements are high enough that snails eat preferred algae and less-preferred algae.
• Algal diversity decreased.
Keystone Species: Summation• Mary Power (1996) : Keystone species exert strong
effects on their community structure, despite low biomass.
In Molles 2007; Fig 17.14
Molles, 2007: Fig. 17.2
Websites for animal information:Penguins: http://www.windows.ucar.edu/tour/link=/people/postcards/
penguin_post.html
Polar Bears: http://www.amnh.org/sciencebulletins/?sid=b.s.polar_bears.20070108&src=/earth/polar/b
http://www.usgs.gov/newsroom/special/polar_bears
CaribouWalrusSeals – Ringed Seals, Fur Seals
http://www.windows.ucar.edu/tour/link=/earth/polar/arctic_marine_life.html
Adaptations…hands on lab exercises…..
Bergman's ruleIn zoology, Bergmann's Rule is a principle that
correlates environmental temperature with body mass in warm-blooded animals. It asserts that within a species, the body mass increases with
latitude and colder climate.
Allen's rule is a biological ‘rule’ proposed by J. A. Allen in 1877. It states that endotherms from colder climates usually have shorter limbs than the equivalent animals from
warmer climates.