**[Abstracts of Invited Papers for Seabirds as Indicators
Symposium]{.underline}**

**FOUR THOUSAND YEARS OF INTERACTION BETWEEN HUMANS AND MARINE BIRDS OF
THE ALEUTIAN ISLANDS**

*Douglas Causey*\*^1^, *Debra G. Corbett*^2^, *Christine Lefèvre*^3^,
and *Arkady B. Savinetsky*^4^, ^1^Department of Biological Sciences,
University of Alaska Anchorage, AK 99508 USA, <dcausey@uaa.alaska.edu>;
^2^U.S. Fish and Wildlife Service, 1011 E. Tudor Road, Anchorage, AK
99503; ^3^Muséum national d'Histoire naturelle, Paris, France; ^4^A. N.
Severtsov Institute of Ecology and Evolution, Russian Academy of
Sciences, 33 Leninsky pr., Moscow 119071, Russia.

A unique window into the biological history of the Aleutian Islands is
provided by the zooarchaeology of early human sites. We focus on the
palaeoavifauna hunted by early Aleuts who inhabited Amchitka and Buldir
islands (central Aleutians), and Shemya Island (western Aleutians) from
about 3,500 years ago to the present. Most of the seabird species
recovered from these early sites varied widely in distribution and
abundance through time and space. Pelagic procellariids such as
Short-tailed Albatrosses (*Phoebastria albatrus*) and Short-tailed
Shearwaters (*Puffinus tenuirostris*) were present and abundant at most
sites and at most times. During periods of increased temperatures and
precipitation (e.g., 650 -- 1100 years before present), nearshore
foragers such as cormorants and parakeet auklets increased in abundance,
but during periods of cooling (e.g., 1800 -- 2100 years before present),
piscivorous birds feeding offshore, such as murres (*Uria* spp.) and
kittiwakes (*Rissa* spp), predominated. Over four millennia, we found
that marine birds were negatively correlated with temperature and
positively correlated with precipitation. We detected hunter-related
depletions of populations breeding in accessible colonies at small
scales of space and time, but we did not observe widespread or long-term
effects. We conclude that local oceanography and regional changes in
prey bases caused by environmental and climate change in the past had a
significant impact on the distribution of Aleutian marine birds.

**SHIFTING SEABIRD DISTRIBUTION AND ABUNDANCE REFLECT A RAPIDLY CHANGING
MARINE ENVIRONMENT IN THE WESTERN ARCTIC**

*George J. Divoky\**^1^ and *Alan M. Springer*^2^, ^1^Institute of
Arctic Biology, University of Alaska, Fairbanks, AK 99775 USA,
<fngjd@uaf.edu>; ^2^Institute of Marine Science, University of Alaska,
AK 99775 USA

While the Bering Land Bridge allowed humans to disperse to the Nearctic
during the Pleistocene, it was a major barrier to seabird dispersal on
the Bering/Chukchi Shelf until approximately ten thousand years ago.
Since then few seabird species have extended their ranges through Bering
Strait, apparently due to climatic and oceanographic disparities between
the subarctic Bering and arctic Chukchi. However, significant changes in
the Arctic Basin over the last four decades have decreased the
latitudinal environmental gradient in the region. Because the Chukchi
Sea lacks a commercial fishery and systematic biological sampling,
changes in seabird distribution and abundance may be the best indicators
of the timing and magnitude of ongoing climate change. Recent
indications of range expansions and population increases include both
puffin species occupying colonies in northern Alaska and increasing
numbers of other Bering Sea alcids on the northern shelf. Cold water
species adversely affected by rapid warming include the Black Guillemot
(*Cepphus grylle*) and Kittlitz's Murrelet (*Brachyramphus
brevirostris*), both of which appear to be decreasing with reductions in
pack ice. We discuss the species likely to have breeding or pelagic
distributions and abundances modified by continued rapid environmental
change and the conditions required for those modifications.

**ADÉLIE PENGUINS AS CLIMATIC INDICATORS IN ANTARCTICA SINCE THE LATE
PLEISTOCENE**

*Steven D. Emslie*\*, Department of Biology and Marine Biology,
University of North Carolina, Wilmington, NC 28403 USA; emslies@uncw.edu

The Adélie Penguin (*Pygoscelis adeliae*) is an excellent indicator
species for climate change and the marine environment in Antarctica.
This species depends largely on sea ice for its foraging and winter
habitat and is circum-Antarctic in distribution. Fossil and subfossil
remains of Adélie Penguins have been recovered from numerous abandoned
colonies in Antarctica since the 1950s. These remains are usually well
preserved, along with dietary remains from guano, due to the cold, dry
conditions in most of Antarctica. Thus, radiocarbon dates on these
remains provide an occupation history of Adélie Penguins for specific
regions that indicates the past presence of (1) open water near the
colony during the austral summer, (2) adequate food within foraging
range of the colony, and (3) sufficient ice-free coastal terrain for
nesting sites. Research to date has indicated that Adélie Penguins
respond to climate change differently in the Antarctic Peninsula
compared to the Ross Sea and East Antarctic regions. Here, this record
is reviewed with recent data from the Ross Sea that suggest that two
long periods of penguin abandonment occurred due to extensive and
persistent sea ice during the Holocene. At least one of these episodes
may have caused a massive population shift in this species at \~2000
years ago. Results also indicate that modern occupations in the Ross Sea
are a relatively recent phenomenon, with most colonies dating to less
than \~1000 years old. These data collectively demonstrate the highly
dynamic and unstable nature of this marine ecosystem in Antarctica.

**SEABIRDS AS INDICATORS OF PREY ABUNDANCE AND CLIMATE IN THE NORTH
SEA**

*Morten Frederiksen^\*^, Mike Harris,* and *Sarah Wanless*, Centre for
Ecology and Hydrology, Hill of Brathens, Banchory, AB31 4BW, UK,
mfr@ceh.ac.uk

The breeding performance of seabirds is generally thought to be linked
to marine environmental conditions, but what exactly does it indicate? A
measured variable (e.g. the breeding success of a given species) will be
affected by at least three types of factors: generic aspects of the
marine environment, species-specific responses to environmental factors
such as food supply, population size or weather, and measurement error.
Arguably, a useful indicator should be responsive mainly to factors
affecting several species in the top predator community. Principal
component analysis offers a way of extracting the common signal from a
number of correlated time series and eliminating confounding factors. We
used principal component analysis to analyse time series of breeding
success of five species of seabirds on the Isle of May, and phenology of
seven species on the Isle of May as well as the Farne Islands 100 km
further south on the E coast of Britain. In each case, we found high
correlations between four species, although not exactly the same set in
each case. The first principal component of breeding success was
positively correlated with the abundance of lesser sandeel (*Ammodytes
marinus*) larvae in the previous year, indicating reliance on 1-year-old
fish. The first principal component of phenology was negatively
correlated with the North Atlantic Oscillation index, indicating that
seabirds use widely available environmental cues to for timing of
breeding. Correlations were at least as strong for principal components
as for the original variables, showing that this method can help select
robust indicators with general applicability.

**SEABIRDS AS INDICATORS OF CONTAMINANTS**

*Robert W. Furness*, Institute of Biomedical and Life Sciences, Graham
Kerr Building, University of Glasgow, Glasgow G12 8QQ, UK,
r.furness@bio.gla.ac.uk

It is often stated that seabirds are good monitors of contaminants
because seabirds are top predators in marine food webs, yet many
seabirds feed at low trophic levels, and only certain contaminants
increase in concentration up food webs. However, seabirds can offer many
advantages because their ecology is well known, they are easy to sample,
they integrate signals over time and spatial scales, and some historical
time series can be developed using archived material. Toxicity of
contaminants to seabirds is generally poorly known. It is unlikely that
changes in seabird demography give useful information on contaminants as
these parameters are affected much more by factors such as food supply,
predators, disturbance and climate. This leaves measurement of
contaminants in/on seabirds as the main focus. Sampling eggs is an
established means of monitoring contaminants, especially
organochlorines. Levels in eggs closely reflect uptake by the female
over days prior to laying, so reflect relatively local contamination.
Feathers may be best for monitoring mercury, and may be useful for other
metals and even for organic contaminants. Analyses of feathers from
museum skins show ca.4-fold increases in mercury exposure in northern
hemisphere marine ecosystems but little increase in the southern
hemisphere, a pattern consistent with predictions based on known
emissions and atmospheric circulation. Current advances include
combining contaminant measurements with stable isotope analysis
(including compound-specific SIA), and selection of appropriate feathers
in relation to the annual molt cycle of seabirds to assess seasonal
patterns of exposure/excretion.

**SEABIRDS AS MONITORS OF ARCTIC CLIMATE CHANGE**

*Anthony J. Gaston\**1 Canadian Wildlife Service, National Wildlife
research Centre, Carleton University, Ottawa, Ontario K1A 0H3, Canada
tony.gaston@ec.gc.ca

Arctic waters are characterized by the presence of seasonal or
year-round ice cover. Seabirds are an important element in Arctic marine
ecosystems where open water persists for 3 or more months of the year.
The position of the seasonal ice zone and the duration of open water is
very sensitive to air temperatures and hence fluctuates strongly with
variation in climate. This makes seabirds adapted to the seasonal ice
zone especially sensitive to climate change. During the past several
decades (since the 1960s) air temperatures in the Arctic, especially the
North American portion, have warmed rapidly, leading to changes in ice
conditions that have resulted in changes to the timing of breeding and
reproductive success of several seabird species. For the Thick-billed
Murre, one of the most abundant species of Arctic seabird, reduction in
summer ice cover in the southern portion of its range have resulted in a
deterioration in conditions for reproduction. Conversely, in northern
parts of its range, conditions may be improving. As ice conditions have
changed, diets have also changed, suggesting that the entire marine
food-web has been transformed. However, because there are no commercial
fisheries in the eastern Canadian Arctic, we have no confirmation of
this. Seabird research in Canada's eastern Arctic demonstrates the power
of seabird studies to illuminate ecosystem changes that would otherwise
be difficult to identify.

**HYPOTHETICO-DEDUCTIVE, PREDICTIVE, AND INDUCTIVE APPROACHES IN SEABIRD
BIOLOGY**

*David Grémillet*, Centre d'Ecologie, Physiologie et Ethologie, Centre
National de la Recherche Scientifique, Strasbourg, France,
<david.gremillet@c-strasbourg.fr>

Most of today's seabird science is hypothesis-driven. This reflects the
frame of mind of researchers in our community and the policy of leading
scientific journals. For some time a second, predictive approach has
been put forward. This research avenue is based on the premise that most
seabirds function as apex predators within marine food webs, and that
they might be used as indicators of marine ecological processes, in
particular in the context of global change. But is this approach really
viable? I address this question using a case study of Arctic cormorants
(*Phalacrocorax carbo*) and insights from the literature. From my own
investigations I conclude that it is difficult to use seabirds as
indicators of climate change without detailed knowledge of their biology
throughout the yearly cycle. More specifically, my studies stress how
little we know about the wintering ecology of seabirds, and how crucial
such knowledge is if we are to integrate these organisms into predictive
ecosystem models. Further, I show that most current seabird studies are
neither hypothetico-deductive, nor predictive, but inductive. This means
that we are facing particularly complex biological systems, and that we
need to observe and explore them first, before we can describe
underlying ecological processes. I therefore conclude that the use of a
predictive approach in seabird science is attractive, yet rather
premature. We should all remain critically aware and publicly advertise
the fact that marine sciences are still in the exploratory phase, and
that seabird research is part of this endeavour.

**SEABIRDS AS INDICATORS OF MARINE ECOSYSTEMS: UNRESOLVED ISSUES OF
SCALE**

*Keith Hamer*, Institute of Integrative and Comparative Biology,
University of Leeds, Miall Building, Leeds LS2 9JT UK,
<k.c.hamer@leeds.ac.uk>

The use of seabirds as indicators of marine environments has advanced
greatly over the past 20 years but there are still many unresolved
problems, especially concerning issues of scale. In particular, we have
only limited answers to the following key questions: (1) at what spatial
scale do different species of seabird respond to variation in marine
environments? (2) what are the scales and magnitudes of changes in
marine environments indicated by observed variation in seabird ecology?
(3) what is the relationship between temporal and spatial scales of
variation? Here I shall present recent data from my research group and
project partners, indicating some possible approaches to addressing
these issues. In particular I shall examine the spatial scale of
correspondence in data from neighbouring colonies, the application of
population dynamic principles to calibrate variation in breeding ecology
against variation in prey availability, and the integration of spatially
and temporally explicit information to examine responses of seabirds to
long-term environmental change. These approaches provide a possible
means of not only gaining a better understanding of past variation in
marine environments but also predicting likely future changes. Two main
conclusions arise from this work: (i) we now have a wealth of
high-quality data for some species at some sites; rapid progress may be
made by developing tools to integrate this information across species
and across networks of monitoring sites; (ii) the geographical
distributions of species contain powerful but often ignored information,
which may provide a framework for integrating temporal and spatial
patterns of variation.

**SEABIRDS AS INDICATORS OF THE MARINE ECOSYSTEM: A PERSPECTIVE FROM
COLONY-BASED MONITORING IN ALASKA**

*Scott A. Hatch,* U.S. Geological Survey, Alaska Science Center, 1011
East Tudor Road, Anchorage, AK 99503 USA, <scott_hatch@usgs.gov>

Thirty years of seabird monitoring in Alaska support a few principles
for using birds as indicators of their environment. Because it is
generally impossible to set up relevant experiments, it is important to
use a comparative approach on species selected for the diverse ways in
which they sample the environment: inshore versus offshore foragers,
divers versus surface feeders, and planktivores versus fish eaters.
Within those categories, it is important to control for genetics and
ecological niche by targeting species that can be monitored concurrently
over a wide geographic range. Several kinds of numerical analysis are
well-suited for quantifying the relevant effects: key factor analysis,
sensitivity analysis, and concordance analysis. Adult survival is a
parameter that integrates much of what the individuals of a population
experience throughout the annual cycle, but to interpret the data it is
important to know where the birds from a given colony go in winter. The
best examples of value-added monitoring are cases where seabirds have
been employed as fish samplers. To realize fully the value of seabirds
as indicators of the marine ecosystem, it is essential to collate the
distilled results of monitoring in a single repository (read Pacific
Seabird Monitoring Database). Hatch\'s top ten list of seabirds to
include in a synoptic program of monitoring intended to capitalize on
seabirds as indicators (North Pacific outside the tropics): northern
fulmar (*Fulmaus glacialis*), Leach\'s storm-petrel (*Oceanodroma
leucorhoa*), fork-tailed storm-petrel (*O. furcata*), pelagic cormorant
(*Phalacrocorax pelagicus*), black-legged kittiwake (*Rissa
tridactyla*), common murre (*Uria aalge*), pigeon guillemot (*Cepphus
columba*), Cassin\'s auklet (*Ptychoramphus aleuticus*), rhinoceros
auklet (*Cerorhinca monocerata*), and tufted puffin (*Fratercula
cirrhata*).

**USING STABLE ISOTOPE MEASUREMENTS OF SEABIRDS AS INDICATORS OF MARINE
ENVIRONMENTS: GOOD NEWS AND BAD**

*Keith A. Hobson\** Environment Canada, 11 Innovation Blvd., Saskatoon,
Saskatchewan, Canada, S7N 3H5, <Keith.Hobson@ec.gc.ca>

The measurement of stable isotope composition of tissues of seabirds has
been shown to indicate seabird trophic level and, in some cases, diet.
This technique can also supply information on relative inputs of prey
derived from inshore or benthically linked vs. offshore or pelagically
linked food webs. More recently, sources of nutrients to reproduction
have been established through isotopic tracing techniques linking diet
and reserves of laying females with their egg macronutrients. Other
areas of interest involve the possibility of delineating origins of
migratory species during the non-breeding season. The combination of
stable isotope and contaminants assays has also provided key information
of the behavior and fate of toxins in marine environments. The
integrative nature of the isotope technique and the possibility of
combining analyses from various tissue types means that this approach
represents a powerful tool to assist in the use of seabirds as
indicators of marine environments, especially when combined with
conventional dietary analyses, trace element and fatty acid assays.
However, there are drawbacks to the technique. Only in simple food webs
can quantitative estimates of individual prey be estimated. A key factor
usually missing from current applications is knowledge of how isotopic
profiles within marine food webs can change temporally and spatially.
Studies must now address these data gaps and new emphasis should be
placed on retrospectively interpreting archived materials and on
establishing long-term isotopic datasets of both seabirds and their prey
at key locations.

**MARINE BIRD COMMUNITIES AT-SEA AS INDICATORS OF SPATIAL AND TEMPORAL
OCEANOGRAPHIC VARIABILITY**

*K. David Hyrenbach* and *George L. Hunt, Jr.,* School of Aquatic and
Fishery Sciences, University of Washington, Seattle, WA 98195, USA;
<khyrenba@u.washington.edu>

Assessing the value of seabirds as indicators of ocean processes
requires an understanding of their scale dependent response to the
physical and biological patterns in their environment. Marine bird
distributions and community structure are influenced by oceanographic
variability at multiple spatial and temporal scales (Hunt & Schneider,
1987). Over macro-mega scales (1000s km) seabird assemblages are related
to large-scale productivity and circulation patterns. More productive
ocean regions sustain higher overall seabird densities, and a
disproportionate amount of diving species with high energetic
requirements. Conversely, low productivity areas sustain impoverished
avifauna dominated by surface-foraging and plunging species with low
energetic requirements. Over smaller coarse - meso scales (1 -- 100s
km), marine bird communities are influenced by the location of breeding
colonies and by physical processes that aggregate and make prey
available close to the surface. These ecological patterns suggest that
distinct seabird assemblages are adapted to exploit specific marine
environments and prey types within particular oceanic water masses and
habitats. Herein, we review the influence of scale dependent processes
in the physical and biological environment of seabirds. We first update
the conclusions outlined by Hunt & Schneider (1987) thirty years ago.
Using this conceptual foundation, we discuss the relevance of marine
bird surveys for monitoring physical and biological processes at-sea,
including water mass distributions, ocean productivity, prey dispersion,
and changing ecosystem structure.

**USING FATTY ACIDS TO STUDY TROPIC PATHWAYS AND DIETS IN SEABIRDS:
QUALITATIVE AND QUANTITATIVE ANALYSES**

*Sara J. Iverson^1,2^ and Alan M. Springer^2^* ^1^Department of Biology,
Dalhousie University, Halifax, Nova Scotia B3H 4J1 Canada; ^2^Institute
of Marine Science, University of Alaska Fairbanks, Fairbanks, AK 99775
USA

The dynamics of predator-prey relationships, the structure of food webs,
and the foraging behavior of individuals are critical to understanding
animal ecology, interactions of predators with their environment, and
effects of environmental variability on ecosystems. Like other top
predators, seabirds are good samplers of prey populations, and their
diets can provide information about lower trophic levels over a range of
spatial and temporal scales. Various methods have been employed to study
seabird diets, the most recent of which uses fatty acids (FAs). This
technique relies on the diversity of FAs and patterns in marine
organisms, coupled with narrow limitations on their biosynthesis,
properties of digestion in monogastric animals, and the prevalence of
large lipid reservoirs in many predators. Through a combination of
controlled feeding trials, field studies, and a traditional approach for
estimating diet, and using calibration methods that account for
metabolism of specific FAs, we have validated the use of FA signatures
for estimating diets of free-ranging seabirds. Results were consistent
with variable habitat structure and other aspects of seabird ecology.
Nevertheless, while we can measure both diet and nutritional quality of
prey using FA analysis, the time frame the diet represents, the ability
to resolve differences in FA signatures between certain prey, and the
magnitude of temporal and spatial variability in FAs of individual prey
species remain less clear. The nature of what seabirds can tell us about
their ecosystems will likely depend on the foraging behavior of a
species and the complexities of the ecosystem it occupies.

**Common and Thick-billed Murre chick diet at the Gannet Islands,
Labrador, 1981-2005: how does it reflect large-scale changes in the
marine environment?**

*Ian L. Jones\** and *colleagues*, Atlantic Cooperative Wildlife Ecology
Research Network, Department of Biology, Memorial University, St.
John's, NL, A1B 3X9 CANADA, ijones@mun.ca

Capelin *Mallotus villosus* and daubed shannies *Leptoclinus*
(*Lumpenus) maculatus* make up most of murre chick diet at the Gannet
Islands, Labrador (53º57'N 56º31'W). A study there during 1981-1983, led
by Tim Birkhead, showed that Common Murre (*Uria aalge*) chicks were fed
predominantly (80%) capelin, while Thick-billed Murre (*U. lomvia*)
chicks were fed predominantly (60-70%) daubed shannies. During
1996-2005, we evaluated how changes in chick diet might be related to
changing environmental conditions, using our long-term chick diet, murre
flight directions, and travel time datasets as well as information
concerning changes in abundance and distribution of capelin in the
northwest Atlantic. Common Murre chicks received more daubed shannies
than capelin in six of our ten study years, while Thick-billed Murre
chicks received \>90% daubed shannies. Most chick meals were probably
captured within 10 km of the colony and productivity remained high
throughout the study. Because we had no data concerning abundance and
distribution of prey species near the Gannet Islands, we were unable to
say whether diet reflected changing prey availability, prey preference
by birds, or both. The proportion of capelin in Common Murre chick diet
was not related to capelin abundance the nearest surveys off NE
Newfoundland. However, the proportion of capelin in Common Murre chick
diet was positively correlated with the North Atlantic Oscillation
index, declined following the period in the early to mid-1990s when
Labrador current water was unusually cold, and declined coincident with
capelin moving to \> 200 m depth according to hydroacoustic surveys off
NE Newfoundland.

**FIELD ENDOCRINOLOGY OF SEABIRDS AND FOOD WEB DYNAMICS IN THE BERING
SEA**

*Alexander Kitaysky*\*, *Evgenia Kitaiskaia, Michael Shultz, Morgan
Benowitz-Fredericks,* and *Thomas Dempsey;* Institute of Arctic Biology,
University of Alaska Fairbanks, 311 Irving 1, Fairbanks, AK, 99775,
U.S.A., <ffask@uaf.edu>

The field endocrinology approach substantially enhances traditional
methods used to assess food availability for marine top-predators.
Traditional methods are indirect and have limited implementation on
large spatial and temporal scales. The field endocrinology approach
provides a direct measure of changes in recent food availability and
foraging history integrated over periods of weeks. Specifically,
temporal changes in food availability can be quantified by measuring
concentrations of the stress hormone corticosterone (cort) in the blood
of undisturbed individuals, and the rise in blood levels of cort in
response to a standardized stressor. A long-term study of seabirds has
revealed that baseline levels of cort were negatively correlated with
current food abundance, whereas acute stress-induced levels of cort were
negatively correlated with food abundance four weeks prior. Cort levels
were also negatively correlated with reproductive performance, and
baseline accurately predicted persistence of individuals affected by
food shortages in a population. Using the field endocrinology approach,
we are investigating the relationships between climate and food web
dynamics at several trophic levels and in several distinct oceanographic
sites in the Bering Sea. Here we report the effects of physical forcing
(ice retreat and wind mixing) on seasonal (May-September) and
inter-annual (1999-2005) dynamics of food availability in planktivorous
and piscivorous seabirds.

**USING SEABIRDS AS INDICATORS IN ECOSYSTEM-BASED MANAGEMENT OF ALASKA
FISHERIES.**

*\*Kathy Kuletz^1^, Jennifer Boldt^2^, Don Dragoo^3^, Vern Byrd^3^, and
David Irons^1^.* ^1^U.S. Fish and Wildlife Service, 1011 E. Tudor Rd.,
Anchorage, AK, 99503, <Kathy_kuletz@fwsl.gov>; ^2^School of Aquatic and
Fisheries Sciences, University of Washington, Bld. 4, 7600 Sand Point
Way NE, Seattle, WA, 98115; ^3^Alaska Maritime National Wildlife Refuge,
95 Sterling Hwy, Homer, AK, 99603.

The Alaska groundfish fishery of the Bering Sea (BS) and Gulf of Alaska
(GOA), is one of the largest in the world. Ecosystem-based management is
a guiding principal for this fishery, as mandated by the
Magnuson-Stevens Act. The goals are to maintain or restore diversity and
sustainability, by assessing historic and future effects of climate and
fishing on ecosystem structure and function. Seabirds are one of the
resources used as ecosystem status indicators, but incorporating
seabirds into ecosystem models and management plans is challenging. Data
comes from seabird colonies monitored by the U.S. Fish and Wildlife
Service (FWS), and from at-sea surveys, which provide information on
distribution, abundance, and seasonal patterns of birds on the fishing
grounds. The NOAA-Fisheries 'Plan Team' works with FWS to incorporate
seabird trend data into ecosystem anomaly charts, and to chart patterns
in seabird chronology, productivity, abundance, and diet. Seabird data
is generally consistent with other indicators of climate shifts that
occurred in 1977, 1989, and 1997. Seabird productivity data indicate
that while there may be regional and decadal patterns, changes are not
uniform across regions, or even among feeding guilds in the same region.
There are usually species or colonies that are exceptions to a regional
pattern, indicative of local environmental effects. Nonetheless, there
are suggestions that regions within both the BS and the GOA may be in
opposition, in terms of conditions beneficial to seabird productivity.
As we improve out understanding of these patterns, we can better
integrate seabirds into ecosystem-based management of fisheries.

**Marine Birds as Samplers of Prey Conditions -- Simple is Useful**

*William A. Montevecchi*, Behavioural and Cognitive Ecology Programme,
Memorial University of Newfoundland, St. John\'s A1B 3X9 Canada

Seabirds sample pelagic (albatrosses, fulmars, petrels, kittiwakes),
near-shore (gannets, gulls, auks) and benthic (cormorants, guillemots,
ducks) environments. To engage seabirds as bio-indicators, a diversity
of species' constraints and capabilities need to be considered and
integrated in multi-species assessments of food web and ecosystem
dynamics. Major problems relating to the exploitation of information
from seabirds about prey conditions relate to 1) the tolerances of
different predator responses, 2) sampling and scaling issues, 3) prey
abundance and availability, 4) prey condition, 5) generalist vs
specialist consumers, 6) parental vs chick diets, 7) qualitative vs
quantitative data and 8) predictive capability. Some of these problems
are resolvable through integrated multi-disciplinary oceanographic
research programs that can provide important information about food web
and ecosystem dynamics. Some are not resolvable. While complexity needs
to be engaged it is not a solution. Qualitative binary data (breeding
success/failure, warm/cold water prey) and their concordances and
dis-concordances can provide robust information when interrogated over
large oceanographic and decadal and longer time scales. The employment
of lightweight devices that measure physiological and physical variables
attached to free-ranging birds during and beyond breeding seasons will
advance indicator predator information capabilities. These studies
permit assessments of a) the intersections of avian predators with
exothermic prey, b) habitat use, c) hotspots and importantly of d)
foraging decisions that are the mechanisms of population responses to
environmental change. Realistic considerations of the utility of avian
assessments of prey and food web conditions need to take into account
the uncertainty in which ecosystem processes are enveloped, and also the
limited predictive capabilities of the enormous efforts of fisheries
biology that have to date been directed at single-species research,
assessment and management.

**DEAD BIRDS DON'T LIE, BUT WHAT ARE THEY REALLY TELLING US?**

*Julia K. Parrish\**, *Kate Litle*, and *Todd Hass*, School of Aquatic
and Fisheries Sciences, University of Washington, Seattle, WA 98195 USA

jparrish@u.washington.edu

Seabirds have long been touted as environmental indicators, because of
their collective potential to integrate top-down, bottom-up, and
anthropogenic signals. But long-term data on live birds is difficult to
collect. Beached bird programs offer a relatively inexpensive
alternative dataset, as programs are largely manned by volunteers. The
Coastal Observation and Seabird Survey Team (COASST) program currently
has over 150 observation beaches spread over 5300 lineal kilometers of
Pacific Northwest coastline. In an ''average' year, volunteers discover
and tag 2000 carcasses of over 55 species. What do dead birds indicate?
(1) geographic patterns pertaining to relative use and relative stress,
(2) temporal and geographic patterns pertaining to breeding phenology,
breeding success, and post-breeding migration, (3) temporal patterns
pertaining to local-to-regional physical forcing at the event (weeks)
and seasonal (months) scales. In combination, these patterns allow us to
define 'normal,' identify significant deviations from mean response, and
rank those factors, both episodic and chronic, most likely to affect
marine bird mortality dynamics in the coastal Pacific Northwest. COASST
data have so far shown that: post-breeding mortality and winterkill
account for 50-75% of beaching; adult-chick ratios in local species such
as the Common Murre (*Uria aalge*) can be used to indicate breeding
success; and deviation from normal beaching patterns, as was the case in
spring-summer 2005 with murres and Brandt's Cormorants (*Phalacrocorax
penicillatus*), can be used to alert the scientific and management
community to the occurrence and impacts of physical forcing factors that
might otherwise be missed.

**TRENDS IN NUMBERS AND BREEDING SUCCESS OF FOUR SPECIES OF SEABIRD ON
UK COASTS**

*Matthew Parsons*, *Mark L. Tasker*\*, *Roddy Mavor* and *P. Ian
Mitchell*, Joint Nature Conservation Committee, Dunnet House, 7 Thistle
Place, Aberdeen, AB10 1UZ, Scotland,
[mark.tasker@jncc.gov.uk](mailto:matt.parsons@jncc.gov.uk)

A co-ordinated monitoring programme has been tracking seabird numbers
and breeding success at a representative sample of colonies around the
UK since 1986. The programme assists the UK in meeting its international
obligations and in monitoring aspects of the health of UK's seas. Four
seabird species, northern fulmar (*Fulmarus glacialis*), black-legged
kittiwake (*Rissa tridactyla*), common guillemot (*Uria aalge*) and
European shag (*Phalacrocorax aristotelis*) comprise nearly half of the
UK's breeding seabird population and each occupies distinctive feeding
niches. Trends in numbers and breeding success through time will be
presented for parts of the UK coast. Breeding success for many
species/areas was at an all time low in 2004, with 2005 being more
productive. A presumed scarcity of young sandeels (*Ammodytes* sp) in
2004, led to widespread starvation of chicks on UK North Sea coasts. In
2005, young sandeels appeared later than usual, and coupled with
alternative feed fish, allowed some chicks to fledge relatively late in
the breeding season. In contrast to the North Sea, breeding success in
NW Scotland was moderate in 2004 but was very poor in 2005. The
available data on diet are inconclusive in this region, but it is
assumed that a food shortage was to blame also.

**SEABIRDS AS INDICATORS OF MARINE FOOD SUPPLIES: CAIRNS REVISITED**

## John F. Piatt, USGS Alaska Science Center, 1011 E. Tudor Rd., Anchorage AK 99503 USA, 

Cairns (1987) predicted that: 1) parameters of seabird biology would
vary in curvilinear fashion with changes in food supply, 2) the range of
densities over which birds responded would be different for each
parameter, and, 3) different seabird species would respond differently
depending on diet and ability to adjust time budgets. When tested with
data collected at colonies of Common Murre and Black-legged Kittiwake in
Cook Inlet, Alaska, these predictions were found to be *mostly* True,
False and True, respectively. Kittiwakes worked hard all the time, and
had little discretionary time to compensate for declining prey density.
Variability in prey abundance translated directly (r^2^=0.89) into
variation in fledging success in a non-linear, threshold relationship.
Murre breeding success was buffered by reallocation of discretionary
time and was a poor indicator of food supply, whereas 'loafing time' at
the colony was a non-linear function (r^2^=0.65) of prey density. For
parameters that were sensitive to fluctuations in food supply, most
responded at similar thresholds of prey density--- presumably because
all responses ultimately depend on the rate of prey acquisition at sea.
Murres and kittiwakes minimized variability in their own body condition
(CV\<10%), and in growth of chicks (CV\<25%) in the face of high
variability in prey abundance (CV=80%). Both species exhibited similar
moderate variability (CV= 25-40%) in laying and hatching success, and in
foraging effort. However, while variability in kittiwake breeding
success (CV=87%) tracked prey variability, murre breeding success did
not (CV=29%). Implications of these results for "seabirds as indicators"
will be discussed.

**Seabirds as indicators of marine ecosystems: from ringing alarm bells
to finding solutions**

*Keith Reid*, British Antarctic Survey, Natural Environment Research
Council, High Cross, Madingley Road, Cambridge, CB3 0ET, UK.
k.reid@bas.ac.uk

In most marine ecosystems, our abilities to measure changes in
lower-trophic levels is often restricted. As integrators, indices of the
performance and population size of upper-trophic level species can
provide the first indications of changes in the ecosystem. The high
profile and amenability to measurement of seabirds has made them a
popular and very successful choice as indicators of ecosystem change.
This role may be considered at two levels; firstly as 'response
indicators' providing an observation that some change in ecosystem
status has occurred, and secondly as 'mechanism indicators' where the
information gathered by seabirds provides insights into the reasons
underlying that observation of change, e.g. by providing data on the
dynamics of key prey species. Marine ecosystems are inherently variable
at a range of spatio-temporal scales; therefore, when examining
causality it is essential to match the scales of response of seabirds to
appropriate ecosystem scales. Where there are multiple responses, e.g.,
those reflecting changes in local foraging conditions to those
reflecting basin-scale processes, a combination of indices at
appropriate scales may provide more powerful indicators of ecosystem
change. The use of seabirds as indicators is justifiably widespread.
However, non-linear responses may create biases towards indicating poor
environmental conditions. As a consequence, seabirds are frequently
perceived as indicators of the failure of management policies.
Opportunities abound, but the challenge for seabird ecologists is to
deliver unbiased policy-relevant outputs than can be integrated into the
successful management of marine resources.

**Seabirds as Ecosystem Indicators in the North Pacific: A Critique of
the Evidence**

*William J. Sydeman* Marine Ecology Division, PRBO Conservation Science,
4990 Shoreline Highway, Stinson Beach, CA 94970 <wsydeman@prbo.org>

For decades marine ornithologists have argued that seabirds are good
indicators of environmental 'health' (i.e., pollution) and ecosystem
constituents (e.g., forage fish stocks). As interest grows in developing
novel approaches to marine conservation, including 'ecosystem
management' and an 'ecosystem-based approach' to fisheries conservation,
there is renewed interest in the role of seabirds as indicators, and its
potential application to management science. There are at least 10 ways
that seabirds can serve as indicators including: (1) seabirds as
indicators of meso- and large-scale (e.g., water mass) marine habitat
characteristics, (2) seabirds as indicators of temporal environmental
variation and climate change, (3) seabirds as indicators of ecosystem
controls (bottom-up, top down, wasp-waist), (4) seabirds as indicators
of fish stocks, (5) seabirds as indicators of zooplankton stocks, (6)
seabirds as indicators of fish and zooplankton communities (i.e., the
multi-species level), (7) seabirds as indicators of contaminants
(metals, OCs, and other contaminants, oil), (8) seabirds as indicators
of harmful algal blooms (HABs), (9) seabirds as indictors of fisheries
and other human impacts on marine ecosystems, and (10) seabirds as
indicators for fisheries management and ecosystem-based management (EBM)
in general. While there are many compelling examples of reliable seabird
indicators, spatial and temporal variation in underlying bio-physical
processes may change the utility of seabird indicators -- e.g., a good
indicator in one decade may be relatively useless in another. Therefore,
understanding scale-dependent responses and fundamental ecological
mechanisms will be required to establish the significance and value of
marine birds as North Pacific ecosystem indicators.

**RESPONSES OF A GENERALIST AND A SPECIALIST DIVER TO THE ANNUAL CHANGE
OF MARINE ENVIRONMENT**

*Yutaka Watanuki\*^1^, Motohiro Ito^1^, Tomohiro Deguchi^2^* ^1^Graduate
school of Fisheries Sciences, Hokkaido University, 3-3-1, Minato,
Hakodate, 041-8611, JAPAN, <ywata@fish.hokudai.ac.jp>, ^2^ Yamashina
Institute for Ornithology, Abiko, Chiba, JAPAN

Breeding seabirds forage within a range from the colony. Therefore,
their diet and breeding success may respond to the annual changes of
local marine environment. On the other hand, the changes of diet of
seabirds may influence local impact on alternative prey species. How
does the ability of seabirds to switch prey constraint these responses
and impact? We compared the responses and food consumptions of a
short-range (\<30 km) generalist diver (Japanese Cormorants) feeding
both on epipelagic and demersal fish and those of a long-range (\<100
km) specialist diver (Rhinoceros Auklets) feeding only on epipelagic
fish breeding on Teuri Island in the Japan/East Sea where the annual
change of the warm Tsushima Current influences the marine ecosystem.
Based on the 14 -17 years data (1984 to 2005), we examined the effects
of the current on their diet and reproductive performance. In years of
strong current flow, hence higher summer SST, both species forage more
on anchovy; indicating that the northward expansion of warm water
determines regional availability of anchovy. While in years of weak
current flow, Rhinoceros Auklets foraged mainly on other epipelagic
species and decreased chick growth rate but Japanese Cormorants foraged
on mid water and demersal fish and maintained breeding success. Breeding
performance of generalist diver did not give us signals of the change of
the current flow. We propose a hypothesis that the current flow affects
local demersal fish population directly and also indirectly through the
impact by top predator.