SCI-04 Natural History of Alaskan
Seabirds
• Session 2: Tuesday, 21 February 2017
Marine
Birds
• Today’s Topics
– Sea Ducks, concluded
– Diving Physiology (Penguins)
– “WATER BIRDS” start:: Penguins,, Tubenosed Seabirds, Pelicans and Cormorants
– Loons: Next lecture
– Photo: humpback whale and shearwaters in
Bering Sea
Scoters: Survival
during molt
• VHF transmitters
– Surf Scoters (n=108)
– White-winged Scoters (n=57)
– Southeast Alaska, British Columbia and
Washington) in 2008 and 2009
• No mortality during molt!
• Key ingredients: safety from predators and
food availability
• Source: Uher-Koch, et al. 2014. Journal of
Wildlife Management 78:1189-1196
Long-tailed Duck (Oldsquaw)
• Small bill, dark wings
• Male: Black breast and long central
tail feathers
• 3 plumages each year
• Uses both wings and feet when
diving
• Deepest diver of sea ducks, to 60
meters (200 feet); benthic prey
• Circumpolar
• In Alaska:
– Breeds in western and northern
Alaska; only sporadically in the Interior
– Winters in Aleutians and along N
Pacific coasts
Long-tailed Ducks:
Population status
• North America:
– Numbers declined 50% in 3 decades
• Yukon-Kuskokwim Delta, 19912004
–
–
–
–
–
Clutch size 7.1 eggs
Nest success 30%
Duckling survival to 30 days: 10%, (0-25%)
Adult female survival: 74%
Model result: Population declining 19%
annually
– Source: Schamber, J. L., et al. 2009. Arctic
62:190-200.
Common Goldeneye
•
•
•
•
Named for bright yellow iris
Nests in tree cavities
Breeds in boreal forest zone
Winters along sea coasts and
inland water bodies
Common Goldeneyes
in nearby nest boxes
• Chena River Recreation
Area
– Duckling survival
• 0.65 in 2002
• 0.68 in 2003
– Adult female annual survival:
0.68
– Both high for this species
– Recesses:
• 3/day
• ~ 100 minutes each
Barrow’s Goldeneye
• Male: Crescent-shaped
white patch in front of eye
• Female: Orange bill,
raised forehead
• Similar in habits to
Common Goldeneye
• Breeding Distribution:
Rocky Mountains to
Interior Alaska
• Winters in rocky coastal
areas
Bufflehead
• Smallest sea duck
• Dives for invertebrates
• Male: White patch on back
of the head; head highly
iridescent
• Cavity nester, prefers
forested wetlands
– Uses Northern Flicker holes
• Winter: highest densities in
shallow coastal bays but
widespread
Mergansers
• Big sea ducks
– among the largest ducks
• Long, pointed, serrated bills
– Diet: mainly fish
– Top predators in aquatic food chains
• Females not as cryptic as most
other female ducks
• Brood parasites and parasitized
Common Merganser
• Male: red bill, dark green head,
white body
• Female: orange bill, rufous
head and neck with white chin
patch, white body
• Cavity Nesters
• At home in both fresh water
and coastal marine waters
• Winters in areas of open water
(“partial migrant”)
Nest departure in
cavity-nesting ducks
• Example: Hooded
Merganser
• Age at departure?
______
• Adaptations:
– Longer and wider caudal
down shaft
– Longer claws
• https://www.youtube.com
/watch?v=bDJw43BJtCE
Red-breasted Merganser
(Akpaksruayook)
• Male: orange bill, dark green head,
white neckband
• Female: Reddish-brown head with
white breast all the way up her chin
• Breeds throughout Alaska
• Nests on ground instead of in tree
cavities
• Winters along sea coasts from
Aleutians to Mexico
Diving Ducks
• Pochards and Scaups
• distinct subfamily, Aythyinae
• Includes Canvasback,
Redhead, Ring-necked Duck,
and scaups
• Foot-propelled divers
• Only Greater Scaup prefers
saltwater in winter: winters
along sea coasts
Greater Scaup
• From “scalp”— Scottish word
for clams, oysters, and mussels
• Winters along sea coasts
• In Interior AK: breeds
inconspicuously at low densities
• Most nest close to lake shores
Seabird Salt Glands
• Problem: Kidneys use 1.5 liters
of H20 to flush salt in 1 liter of
salt water: losing proposition
• All seabirds have salt glands:
– Paired, above eyes
– Excess salts secreted
– Drips from beak or sneezed from
nostrils (tubenoses only)
– Highly effective (90% of salt
intake)
– (Diagram: Gull)
All Seabirds except sea ducks,
phalaropes
• Plumages: Monomorphic
• Body Size: Males average
slightly larger, great overlap
between males and females
• Typically can’t distinguish
males from females except
by copulation positions
• Both sexes share
incubation, brooding,
feeding of young
• If showy: “mutual sexual
selection”
Seabird Phylogeny: Current View
• Diverse ancestries
• A. “Water birds”
–
–
–
–
Tube-noses
Penguins
Pelicans and Cormorants
Loons
• B. Grebes (Flamingos)
• C. Shorebirds and allies
– Charadriiformes (part)
• Laridae
• Alcidae
• Two types:
– Foot-propelled
– Wing-propelled
– Within both:
CONVERGENCE
“Water birds”
• Closest relatives:
– Penguins
– Tube-nosed Seabirds
• Next-closest:
– Pelicans and Cormorants
• Then: Loons
• Where do gulls and auks fit in?
Penguins: Diving Physiology
• Dive speed
– Typically ~8 km/hour (5 mph)
• Dive duration
– Most several minutes, followed by
only brief rest, recovery periods at
surface
• Keys:
– “Super” Hemoglobin to bind oxygen in
lungs
– Blood, muscle myoglobin binds O2
– Bradycardia to 5 beats/minute
• Avoiding the bends?
The bends
• The deeper the dive, the
greater the pressure
• As pressure increases,
air molecules (mostly N2)
dissolve in the blood
• Back to surface:
dissolved air molecules
can form bubbles
• How do deep-diving sea
birds avoid the bends
(formation of N2
bubbles)?
Penguins:
DEEP dives
• Oxygen pressure in
lungs drops very low
• HOW so different from
humans?
• Hint: Volume vs
inflation pressure:
– Lungs: little change
– Air sacs: major increase
Avian Respiration
• One-way flow through lungs
• System of air sacs (no gas
exchange)
• Figure: respiratory systems of
Adélie, King and Emperor
penguins
– Yellow: Trachea and lungs
– Blue: anterior air sacs
– Red: posterior air sacs
• Are air sacs a reservoir for
inhaled air during deep
dives?
Penguins
• Order Sphenisciformes
• Southern Hemisphere only,
farthest north: Galapagos
• Flightless?
• Wing-propelled divers, to 800
meters
• Feathers grow all over body,
not in tracts (all other birds)
• Plumage dense, waterproof
• Evolution?
Penguin body size
• Earliest
fossils: similar
to King
Penguin
• Eocene
Epoch (56-34
mya)
– Some much
larger and
heavier than
Emperor
Penguin (D)
Penguin FLIGHT!
• http://www.youtube.com/watch?v=9dfWzp7r
YR4&feature=related
• http://www.youtube.com/watch?v=lzhDsojoq
k8&feature=channel
Penguin relatives
• Penguins evolved from flying, tube-nosed
seabird ancestors (Order
Procellariiformes)
– DNA analyses
– Fossils: Both fossil penguins and Little
Penguin have tubular nostrils like the
tubenoses (photo: Northern Fulmar)
– Behavior: similar bill-fencing courtship
displays and methods of feeding
young
Order Procellariiformes
• Albatrosses, Petrels and Shearwaters,
Storm Petrels, Diving Petrels
• 4 families, 26 genera, 112 species
• tubular nostrils and a distinctly hooked
bill
• Both Northern and Southern
Hemispheres
• Highly pelagic
• most feed in surface waters
• Smallest: 6-inch Least Storm Petrel
• Largest: Wandering Albatross:
wingspan nearly 12 feet
• Photo: Great-winged Petrel (Australia)
Tubenoses: Flight
• Wings typically long, held
stiffly, and used for “dynamic
soaring” over the ocean
Tubenoses: Sense of Smell
• Very well-developed
• Large olfactory bulbs in
brain
• Why?
– Location of zooplankton
(phytoplankton release
dimethyl sulfide when
being consumed by
zooplankton)
– Some species: finding
nest burrow at night
Diving Petrels
• Very short wings, wingpropelled diving
• Can also fly in air
• Analogue to
evolutionary
intermediate between
tubenoses to penguins
• Southern Hemisphere
only: WHY?
_________
Midway Atoll
• An abundance of albatrosses
• Photo: All 3 species breeding in N Pacific
– Left: Laysan 460,000 (>70% of world
population)
– Middle: Black-footed: 25,000
– Right: Short-tailed: 1-3 each year
Short-tailed Albatross
• Non-breeding range extends
into northern Bering Sea
• Late 19th Century: 5 million
killed by feather hunters
• Toroshima Island: 1939
volcanic eruption, lava flow
over breeding grounds; 10
pairs remained
• Now about 2,200 all
breeding on Toroshima
• Colonizing Midway?
Laysan Albatross
• Description:
– Relatively small
• Abundant: 2.5 million
• Breeds on NW
Hawaiian Islands
• Recently colonized
Kauai
• Non-breeding: to shelf
break in Bering Sea
• Foods: squid, flying
fish, fish, at surface
Oldest-known bird
• Wisdom, Laysan
Albatross
• Female
• At least 65 years-old
• Breeds on Midway
• December 2016: Laid
41st egg (maximum: 1
egg/year)
Laysan Albatrosses on Kauai
• Osterlund in “Holy Moli”:
– “Nearest colony 1,000 miles away (Midway)”
– Vs. Rice and Kenyon (1962): 500 on nearby
Niihau
• Barking Sands:
– First colonized in 1980’s
– Fear of collision with military aircraft
– Relocations to Kilauea Lighthouse
• Adults: unsuccessful
• Eggs: successful (also eggs to Oahu)
• https://www.fws.gov/Endangered/news/episodes/buFall2015/coverstory/index.html
Black-footed Albatross
• Numbers: 130,000
• Most breed on NW
Hawaiian Islands
• To southern Bering
Sea
• Concern: catches in
longline fisheries
Family Procellariidae:
Shearwaters and Petrels
• Mottled Petrel
• “Near Threatened”
– Breeds off islands
near New Zealand
– “Winters” in North
Pacific and Bering
Sea during our
summer
– Numbers: 10’s of
1,000’s
Northern Fulmar
• Northern Oceans
• Dark to light color morphs
– Light morphs predominate in
Bering Sea
•
•
•
•
•
•
Stocky build, rounded wings
Alaska population ~1.4 million
Worldwide: 10-30 million
Age at 1st breeding: 8-9 years
Long-lived, to 30 years
Foods:
– fishes, squid, zooplankton
– Benefit from fish waste
Sooty Shearwater
• Abundant but
declining
• Breeds in Southern
Hemisphere
• “Winters” in North
Pacific (to southern
Bering Sea) and
North Atlantic during
our summer
Short-tailed Shearwater
• Another “Muttonbird”: chicks
harvested
• Very similar to Sooty
Shearwater,bill shorter
• Breeds in Australian waters
• “Winters” in North Pacific, to
Beaufort Sea!
• Nonbreeding FLOCKS in Alaskan
waters may number in the millions
• Feeds on crustaceans; plunges
and surface dives
• Photo: Unimak Pass, Alaska
Migratory anomalies
• Almost no species breed in
the southern hemisphere
and winter in the northern
hemisphere
• Notable exceptions:
Mottled Petrels, Sooty and
Short-tailed Shearwaters
• Why rare in seabirds?
– must cross unproductive
tropical and subtropical
waters
– Figure: primary productivity
Keys to marine productivity
• I. Enough sunlight
for photosynthesis
by phytoplankton
and plants (euphotic
zone, to about 200
m depth)
Key ingredient II: Oxygen
• Dissolves more readily
in colder water
• Dissolves more readily
in less salty water
• Where is concentration
highest? ________
Key Ingredient III:
Nitrogen
• N2
– 70% of atmosphere
– Inaccessible to most
organisms
– Notable exceptions:
Nitrogen-fixing bacteria
• Interior Alaska: Frankia
nodules on alder roots
• Oceans: cyanobacteria
– Fixed nitrogen: sinks to
bottom if no upwelling
Bering and Chukchi:
HIGH productivity
• Cold currents flowing
onto shallow continental
shelf bring nitrogen into
euphotic zone
• Since cold: high oxygen
content
• All essential ingredients
present
• Currents advect plankton
northward
Family Hydrobatidae:
Storm-Petrels
• Small-bodied
• Long-lived (20-30 years)
• Only nocturnal mate
exchanges at nest
• Hover close to surface and
patter or hop on top of
waves (“walk on water”)
• PHOTOS: Wilson’s Stormpetrel
Fork-tailed
Storm-Petrel
• North Pacific
Ocean only, to
Aleutian Islands
• 5-10 million
• Ground burrows
in forested areas
• Highly pelagic
• Foods:
crustaceans,
fishes, at surface
Leach’s Storm-Petrel
• 8 million; Note sizes
of red circles
• Northern
Hemisphere, both
oceans, to Aleutian
Islands in N Pacific
• Average life span:
20 years (to > 30
years)
Leach’s Storm Petrel
• Can detect concentrations of
dimethyl sulfide up to 12 km from
source
• Locate their own nesting burrows
in complete darkness by smell