

Organochlorine residue data are available from various 
coastal regions, particularly of the United States and 
Europe (Ohlendorf et al. 1978b). However, there have 
been relatively few studies of chlorinated hydrocarbon 
contamination of marine birds in Alaska and other areas 
of the northern North Pacific. 
From 1973 through 1976 we collected eggs of seabirds 
nesting in Alaska to measure environmental contaminants 
and to determine differences in residue concentrations 
among eggs from different nesting sites and from different 
species. Emphasis was directed at collecting eggs of north- 
ern fulmars (Fulmarus glacialis), fork-tailed storm-petrels 
(Oceanodroma furcata), pelagic cormorants (Phalacro- 
corax pelagicus), glaucous-winged gulls (Larus glauces- 
cens), black-legged kittiwakes (Rissa tridactyla), common 
murres (Uria aalge), and tufted puffins (Lunda cirrhata) 
because of differences in both their food habits and ranges, 
and because of logistical considerations. Eggs of other 
marine birds were collected opportunistically. We report 
here the findings of the analyses of these eggs and interpret 
their significance. 
It is unlikely that any seabirds remain uncontaminated 
by the synthetic organochlorine compounds that have be- 
come ubiquitous pollutants (see Ohlendorf et al. 1978b for 
review). The most abundant (and universal) of these com- 
pounds is frequently p,p'-DDE, a metabolite of p,p'-DDT, 
which is the principal component of the commercial insec- 
ticidal mixture. Polychlorinated biphenyls (PCB’s), or 
chlorobiphenyls, are occasionally found in seabirds at con- 
centrations that may induce adverse effects. Other syn- 
thetic organochlorine compounds have been detected in 
seabirds, but almost always at levels substantially lower 
than those of the DDT and PCB compounds. 
Some researchers (see Vermeer and Reynolds 1970; 
Prestt 1971; Dunnet 1977; Vermeer and Peakall 1977; 
Ohlendorf et al. 1978b; and Ohlendorf 1982) have sug- 
gested that birds may serve as useful indicators of marine 
pollution on a global scale for several reasons: (1) They 
occur in most estuarine and marine ecosystems, are often 
numerous, and feed on a wide range of marine organisms. 
(2) Most species nest colonially and lay large distinctively 
marked eggs that can be readily analyzed. (3) Certain 
species are sufficiently conspicuous to enable measurement 
in changes in numbers and determine population changes; 
populations with strong traditions for using particular 
areas for breeding, migration, and wintering permit valid 
temporal and regional comparisons. (4) Many species are 
widely distributed and may consequently indicate local 
environmental changes in many areas throughout their 
ranges. (5) Because certain seabirds are at the top of food 
webs (terminal consumers), they accumulate an array of 
environmental pollutants. (6) Certain birds are physio- 
logically susceptible to particular chemicals, and the ob- 
servable responses to contaminants (e.g., changes in num- 
bers, reproductive success, behavior, and colony attend- 
ance) are often more conspicuous than in other indicator 
organisms. 
Eggs serve as particularly useful sample units for analy- 
sis of organochlorines and certain heavy metals—espe- 
cially mercury — because they constitute distinct units for 
comparison, do not decompose rapidly, and are easily col- 
lected and handled. Some seabird species lay an additional 
clutch if the first is removed; eggs from those species may 
thus be taken without adversely affecting populations. 
This characteristic is of particular importance because 
studies are sometimes not begun until it is apparent that a 
population is declining (Vermeer and Reynolds 1970; 
Prestt 1971). 
Organochlorine concentrations in the egg serve as an 
index to whole-body concentrations found in the female at 
the time the egg was laid or those in her diet (Cummings et 
al. 1966; Vermeer and Reynolds 1970; Haegele and Hud- 
son 1974; Driver et al. 1976; Longcore and Stendell 1977; 
Kan and Jonker-den Rooyen 1978; Custer and Heinz 1980; 
Haseltine et al. 1980). Although some microbes have the 
ability to metabolize organochlorine pesticides under cer- 
tain conditions (Matsumura 1974), putrifaction does not 
significantly affect residue analysis for DDT and its 
metabolites (Mulhern and Reichel 1970). During incuba- 
tion, however, the developing embryo appears to metabo- 
lize DDT to DDD and DDE (Abou-Donia and Menzel 
1968; Blus et al. 1974). Chemical residue concentrations 
can be adjusted for the loss of moisture and lipids that 
occurs during incubation (Stickel et al. 1973). For various 
reasons, organochlorine residue concentrations in whole 
egg contents (combined yolk, albumen, and developing 
embryo) are best expressed on a fresh wet-weight basis; 
they should be expressed on lipid-weight basis only if the 
degree of incubation is known and stated (Stickel et al. 
1973; Peakall and Gilman 1979). 
Methods 
Eggs were collected at 18 sites in Alaska, divided among 
five regions (Table 1, Fig. 1), in 1973-76. Because fiscal 
limitations precluded a systematic collection of eggs, the 
collections were made by persons visiting the areas or con- 
ducting investigations there for other purposes (collectors 
are listed in Appendix I). 
Entire clutches were collected; eggs were individually 
wrapped in aluminum foil and placed in plastic containers 
to retard moisture loss. They were shipped to the Patuxent 
Wildlife Research Center and refrigerated until they could 
be processed. Contents were then removed, placed into 
chemically cleaned jars, and frozen pending analysis. 
Only one egg per clutch was analyzed. 
Egg volumes were measured to the nearest 1.0 mL by 
water displacement before the contents were removed. 
Residue concentrations were adjusted to fresh wet weight, 
assuming a specific gravity of 1.0 as suggested by Stickel 
et al. (1973). 
Preparation of the egg samples and the subsequent sol- 
vent extraction, lipid removal, and separation of pesticides 
