Animals of the Poles Presented by Kate Devlin. Antarctic krill, Euphausia superba; Actual Size: 58...

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.