Offshore Surveys

A Marbled Murrelet in flight offshore from Crescent City

This week I got a little break from banding and got to participate in the offshore monitoring of seabirds. We left out of the port of Crescent City, CA at about 7:30AM in a 20' Boston Whaler and headed out into the thick fog. The surveys consist of 200m wide by 8Km transects which we follow at about 15 miles/hour navigating by GPS. There are 2 observers/data recorders (port and starboard) and one driver and we switch positions after every transect. Basically we just ride along with a voice recorder and note any sea birds seen. We can ask the driver to stop and approach questionable birds, as well as marbled murrelets which require additional data. These Federally Endangered birds, relatives to puffins, are unique in that they nest inland at distances of up to 50 miles in the branches of old growth conifers most notably the coastal redwoods. They are severely threatened due to the uncontrolled logging of pacific old growth forest that has occurred up until recently. Recent threats also include nest predation, mainly by corvids (jays and ravens). The single egg must be incubated for 30 days and fed for 40 days (from the ocean) before the chick can fledge. I spoke to a student at Humboldt State University who works in a lab where they have a camera mounted on a marbled murrelet nest, and she told me that 6 of the last 7 years the single egg has been pilfered by a Steller's Jay. These Jay's are able to access many more murrelet nests than previously since they are often lured into the forests by messy campers and picnic sites. Forest fragmentation has also exposed the murrelet nests to more danger. There is a plan in effect to save the murrelets but sadly after speaking with many of the researchers here it seems grim for the murrelets whose numbers are decreasing at a rate of around 3%-4% annually. The California population was estimated at just 6500 birds in 1995 (Miller and Ralph, 1995) and has most surely dropped. Having said that, I did in 2 days of surveying, see about 75 marbled murrelets including 2 juvenile birds.

Offshore Crescent City:
surfbird 30
surf scoter 2
white winged scoter 3
double crested cormorant 6
brandts cormorant 200
pelagic cormorant 20
MARBLED MURRELET 65
common murre 2000
RHINOCEROUS AUKLET 85
pigeon guillemont 40
SOOTY SHEARWATER 3
PINK-FOOTED SHEARWATER 2
barn swallow 6
tree swallow 5
western gull 300
clarks grebe
western grebe
pacific loon 4
rock dove 1
ruddy turnstone 1
black oystercatcher 1

Offshore Humboldt Bay:
white winged scoter
double crested cormorant 20
brandts cormorant 125
common murre 750
MARBLED MURRELET 8
PARASITIC JAEGER 2
SOOTY SHEARWATER 1
JAEGER SPP. 2
Elegant Tern 55
western gull 115
california gull 2
caspian tern 3
red necked phalarope 8
barn swallow
RHINOCEROUS AUKLET 2
pigeon guillemont 3

Now some photos: These are bad and blurry because:
The boat was super shaky with 6 ft. swells?
The birds are little targets for a big lens in a big sea?
The fog was thick, and when it cleared it was overcast?
Nonetheless these are very cool birds that are hard to observe so even a bad photo is interesting

A Rhinocerous Auklet off the coast of Crescent City

Rhinocerous Auklet

Common Murre with chick

Different Common Murre with chick

Brandt's Cormorant

Pigeon Guillemont

Marbled Murrelet pair displaying courtship behavior

I did band birds this week on Friday at Mad River and although it was rather slow (only 16 birds) we did catch many beautiful freshly molted Wilson's Warbler HY birds (one of my favorite warblers)

Mad River, July 31

Wilson's Warbler 5
Wrentit 4
Song Sparrow 1
Macgillivray's Warbler 1
Swainson's Thrush 4
Hermit Thrush 1

And a few photos I have taken over the summer:

Spotted Sandpiper in alternate breeding plumage. Trinity River near Douglas City, CA

A Common Yellowthroat captured and banded at Salmon Creek near Eureka, CA

A Western Wood Pewee near Rocky Point, OR