Seabirds
Procellariiformes , Gaviiformes , Sphenisciformes , Pelecaniformes , and
Charadriiformes = 320 spp.
Water > 67% Earth ’ s surface but seabirds ~ 3% bird spp
Some differences between sea and landbirds:
- Most feed from the ocean
- Nasal glands for expelling brine
- Vary in their dependence of land, but all must return to land to breed
- Others hardly ever settle on water (Sooty Tern, frigates) and continuously on wing away from land
- Active at night

Order: PROCELLARIIFORMES
Tube-nosed Seabirds
4 Families
Diomedeidae – Albatrosses
No. Pacific and So. Oceans
2 Genera, 14 Spp
(All threatened or worse)
Procellariidae – Shearwaters, petrels, and fulmars
All Oceans
14 Genera, 76 Spp
Hydrobatidae – Storm petrels
All Oceans
7 Genera, 21 Spp
Pelacanoididae – Diving petrels
So. Oceans
1 Genera, 4 Spp
Wandering Albatross – Diomedea exclans

Northern Fulmar – Fulmarus glacialis
Wilson ’ s Storm Petrel –
Oceanites oceanicus
Peruvian Diving-petrel
Pelecanoides garnotii
– Greater Shearwater –
Puffinus gravis

Sulidae – Boobies, Gannets
All Oceans
3 Genera, 9 Spp
Northern Gannet – Morus bassanus
Order: PELECANIFORMES
Blue-footed Booby –
Sula nebouxii

Phalacrocoracidae – Cormorants
All Continents and Oceans
1 Genera, 38 Spp

Order: CHARADRIIFORMES I: non-seabirds
Shorebirds, Gulls, and allies
18 Families
85 Genera
> 300 Spp
American oystercatcher –
Haematopus palliatus
Haematopodidae: 1G, 11 Spp, Worldwide
Spotted Dikkop – Burhinus capensis
Burhinidae: 1G, 9 Spp, except NA

American Avocet
–
Recurvirostra americana
Recurvirostridae: 3G, 10 Spp, All continents
Double-banded Sandgrouse –
Pterocles binictus
Pteroclidae: 2G, 16 Spp, Old World

Scolopacidae – sandpipers and allies
21 Genera, 88 Spp - Worldwide
Wilson ’ s phalarope
–
Phalaropus tricolor
Upland Sandpiper Bartramia longicauda
Greater Painted-snipe –
Rostratula benghalensis

Charadriidae – plovers, lapwings
10 Genera, 66 Spp - Worldwide
Blacksmith Plover –
Vanellus armatus
Black-bellied Plover – Pluvialis squatarola
Hudsonian Godwit –
Limosa haemastica

Rhynchokinesis
Independent opening of the distal upper jaw
Common Snipe
Hudsonian Godwit –
Limosa haemastica

Niche Differentiation – Bill size and shape determines habitat and prey

Stercorariidae
CHARADRIIFORMES II: seabirds
– Jaegers
2G, 8 Spp, Polar regions
Laridae – Gulls and terns
13 Genera, 95 Spp - Worldwide
Parasitic Jaeger –
Stercorarius parasiticus
Ross Gull –
Rhodostethia rosea
Black-legged Kittiwake –
Rissa tridactyla
Little Tern –
Sterna albifrons

Alcidae – Auks, murres, puffins
12 Genera, 23 Spp – Northern Oceans
Razorbill – Alca torda
Tufted Puffin – Fratercula cirrhata

Order: SPHENISCIFORMES
Spheniscidae
Penguins – Southern Oceans
6 Genera
17 Spp (~50% threatened or worse)

Parallel Evolution wing-propelled divers in the two hemispheres gull razorbill
Great auk
Penguin

Niche separation in the Seabirds

Distribution of seabirds is governed by :
(1) latitudinal marine zones
(2) distribution of food in the zone
(3) nesting sites - safe nesting cliffs, islands, promontories
(4) distance of nest to food sources
Another difference between land and seabirds is distance flown to food
– 100m to several km for landbirds to 10s, 100s, or 1000s km for seabirds
Procellariiformes are the most pelagic and the capacity to exploit distant food supplies is aided by:
(1) lower body temp (38 vs 41 degrees)
(2) Subdermal fat and stomach oil
(3) Flying style (dynamic and slope soaring)
(4) Well-developed olfaction
(5) Young resist chilling and become torpid

Marine zones and productivity
9 marine water zones (life zones)
Cold water has more nutrients and O
2 and thus support more life
Weak winds in the tropics means productivity is 1% that of temperate coastal water. The highest productivity being in polar areas and around continental shelves.

Seabird distribution across marine zones
The wide expanse and productivity cold southern oceans is where seabirds reach their max abundance of individuals. Procellariiforms, dominate this region
– partially due to short food chains, krill, and loss of krill-feeding whales.

Auks, penguins, diving petrels are the only major seabirds that failed to colonize both hemispheres – and interestingly they also show the most striking evolutionary convergence.
All spp hunt by “ flying ” underwater and this may explain their absence form cold water.
A change in water temp of 5 to 15 degrees doubles the swimming speed of exothermic fish, but doesn ’ t change the speed of endothermic birds.

Foraging zones (2-dimensional)
- Inshore (6-8 km from the sea)
- Offshore (coast to edge of continental shelf) - Pelagic (over deep ocean)
European Shag: 7 km trips of 6 hrs
(Scotland)
Common Tern: 30 km trips of 2 hrs
(Wadden Sea)
Black-legged Kittiwake: up to 60 km and 6 hrs
(Alaska)
Northern Gannets: 232 km (540 max) in 13-84 hrs
(Scotland)
Wandering Albatross
S. Georgia to S. Brazil
(26 ° S to 67 ° S)
S. Chile to S. Indian Ocean
(17 ° W to 85 ° W)
6091 km/trip; 1534 km from nest gone for 11.6 days
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Fasting (for young and parent left behind) is associated with these trips
Galapagos penguin: < 3 days
Magellenic and King: 25-40 days
Emperor: walk 150-180 km to open water, forage 500 km, fast for >110 days
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Foraging zones (3-dimensional)
Species differ in whether they obtain food below the surface and the depths and length of time they can remain submerged
Here, auks and penguins are the most marine spp.
The best human diver can dive 100 m in 4 minutes.
King and Emperor Penguins: 304 and 534 m, respectively and 7.5 and 15.8 min, respectively

Most seabirds nest colonially and sometimes in great numbers, In general, nest-sites are of much greater biogeographic importance and limiting factor to population size than is the case for landbirds.

Breeding and life history
Most seabirds are long-lived (30 or more years) and don ’ t breed until several years old. Breeding may take a long time (up to 1 yr in large albatrosses) and occurs only every other year.
Many (Procellarids, Alcids) lay a single large egg (up to 25% of adult mass)
Both parents incubate or otherwise care for young
Most (Alcids are an exception) regurgitate partially digested food or provide stomach oil
Pairbonds remain as long as both parents are alive, although divorce can occur, most frequently after unsuccessful breeding.
This pattern of life history (reproductive and survivorship schedule) means that most populations are slow-growing and vulnerable to sudden collapses in population size
(i.e., recovery is very long). Alternatively, their long life spans allow them to buffer short-term collapses in food supply that shut-down reproduction (e.g., El Ni ńo events).