## Relationships between boat harbors, fish processing, contaminants, and wintering Steller’s eiders and Harlequin Ducks in the Eastern Aleutian Islands.

2004 PROGRESS REPORT

Photo by Jeff Wasley 

## United States Department of the Interior U.S. Geological Survey

Alaska Science Center 1011 East Tudor Road Anchorage, Alaska 99503Wintering Steller’s Eiders at Dutch Harbor 2



### INTRODUCTION

Declines of Steller’s eiders ( Polysticta stelleri ) on their breeding areas in Alaska have resulted in the North American breeding population being listed as Threatened under the provisions of the Endangered Species Act (Fox et al. 1997, Flint et al. 2000). Activities such as small boat harbor developments and increased seafood processing may impact eiders that wi nter along the Alaska
Peninsula and eastern Aleutian Is lands. Adverse effects may incl ude: displacement from foraging sites, destruction of foraging habitat, and exposure to petrol eum products or seafood processing wastes. However, information on Steller’s eiders and their wintering site fidelity, home range, and migration patterns is limite d. Understanding patterns of site fidelity, home range, and habitat use by wintering populations is essential to predicting the effect of disturbance, habitat loss, or exposure to contaminants.

Steller’s eiders tend to winter in areas of industrial deve lopment, particularly near seafood processing plants and associated boat harbors (Hoffman 2000, 2001). Eiders may be attracted to these areas because of the presence of ice-fr ee waters and the increased primary productivity resulting from eutrophication associated w ith seafood processing wastewater (Persson et al

. 1995, Dachs et al . 2000, Gunnarsson et al . 2000, Skei et al . 2000.) However, industrial activities around these areas also increase the probability of exposure to contaminants, particularly petroleum-based products. Further, past milita ry activity along the Alaska Peninsula and Aleutian Islands may be another source of organi c contamination, particularly PCBs or DDT. Given the historical background and the possibility of increased eutrophication, these industrial areas may function as ‘traps’ that attract large concentrations of wintering seaducks, which are then exposed to harmful levels of contaminants.

OBJECTIVES

(1) Radio-mark 30 Steller’s ei ders and 30 Harlequin ducks ( Histrionicus histrionicus ) from
several locations around Dutch Harbor and track i ndividuals to assess site fidelity, behavior, and patterns of movement.

(2) Determine patterns of habitat use and foraging locations in relation to discharged wastewater from sewage, fish processing, and harbor developments.Wintering Steller’s Eiders at Dutch Harbor 3



### (3) Obtain blood serum, whole blood, cloacal swab s, and fecal samples from wintering sea ducks to determine exposure to contaminants, viruse s, and to assess general health indices.

(4) Determine concentrations of bacteria, viruses, and trace elements in water and Blue mussels
collected at several locations around Dutc h Harbor used by wintering sea ducks.

Figure 2. Floating mist net capture setup. METHODS Figure 1. Location of study.
Captures

From 23 January to 31 March 2004, a study team consisting of 1-3 research biologists and 1- 2 biological technicians conducted fieldwork at Amaknak/Unalaska Islands, (Dutch Harbor) Alaska (Figure 1). Between 26 January and 3 February, we captured du cks at five sites around
Dutch Harbor. Sites incl uded: 1) the south end of Hog Island, 2) Airport Beach just south of the runway, 3) a bay along Ai rport Beach Road at the outflow for processing waste from Unisea and the municipal sewage system, 4) Little South America (just south of the bridge connecting Amaknak and Unalaska Islands), and 5) inner Captain’s Bay by the islands at the south end of the Bay. The Little South America location is one of the proposed sites for a new harbor development.

As in previous years, we used floating mist nets with decoys sets to cap ture wintering sea ducks (Figure 2). We used tw o inflatable boats and a skiff to drive rafting birds towards the net, to remove captured individuals, and to transportWintering Steller’s Eiders at Dutch Harbor 4



### birds for immediate processing.

Radio Tracking

All captured birds were banded, weighed, sexed, a nd aged. We attached 10 g radio transmitters using the sub-cutaneous prong and suture transmitter attachment described by Peitz et. al (1995).
We tracked radio-marked ducks from 26 Janua ry through 26 March with telemetry receiving equipment mounted in pick-up trucks. We sca nned for all transmitters multiple times per day from several locations around Dutch Harbor. For every transmitter detected, we recorded the time, location, strength of signal, and activity (d iving or roosting). Between 22 February and 26 March we collected simultaneous bearing from tr ucks in two locations for all radios that provided clear signals to both trucks. We then used the bear ing data to calculate more precise locations using simple triangulation.

Sampling for Associated Studies.

Blood samples and cloacal swabs were taken usin g standard techniques. Blood was transferred to non-heparin tubes for serum and to hepari n tubes for whole blood. Serum samples were centrifuged (10 minutes) 1-6 hours after collection, tran sferred to cryovials, and frozen in nitrogen dry shippers. Whole blood samples were frozen in a conventio nal freezer and cloacal swab samples were transferred to virus storage media and frozen with the serum samples. Additionally, we collected fecal samples from most birds. These were preserved in 10% Formalin solution for parasite analysis. We also collected water and Blue mussels at each of the five capture sites.

RESULTS


## Captures

Between 26 January and 3 February we caught 88 birds includi ng Steller’s Eiders, Harlequin Ducks, Black Scoters, White-winged Scoters, and Long-tailed Ducks from five sites around Dutch Harbor (Figure 1, Table 1) . We radio-marked 28 Steller’s eiders (8 male, 20 female) and 32 Harlequin ducks (22 male, 10 female).Wintering Steller’s Eiders at Dutch Harbor 5

Table 1. Sample sizes of birds captured in Dutch Harbor 2004 by location.

Species Sex Age Hog Island Airport Sewage Outflow Little South America Captain’s Bay Steller’s eider Male AHY 2 1 2 5 juv Female AHY 9 4 1 6 juv 1 Harlequin duck Male AHY 5 2 3 4 4 juv 1 4 1 2 2 Female AHY 1 4 2 2 juv 2 1 1 2 Black scoter Male AHY 1 1 juv Female AHY 1 1 juv 1 Male AHY 1 1 White-winged scoter juv 2 Female AHY 1 juv 2 Long-tailed duck Male juv 1 Female juv 1



### Radio Tracking

We detected all 60 radio-marked ducks after re lease. During February we recovered twelve transmitters (six per species) from dead birds (see Mortality section) or shed from live birds. Of the remaining transmitters all Steller’s eiders we re detected through February and all but four were detected through 20 March. Only two Harl equin ducks were not heard through 20 March. The mean number of detections per Steller’s eider was 214.4 (s.e. = 25.4) and per Harlequin duck was 192.3 (s.e.=21.7) (Table 2).Wintering Steller’s Eiders at Dutch Harbor 6



### Mortality
While radio tracking, we detected the mortality of four Steller’s eiders and six Harlequin ducks.
We recovered four fresh carcasses (3 eider, 1 Harlequin duck) fr om fox caches. The recovered
carcasses were frozen in a conventional freezer and then shipped to Dr.Tuula Holmen at the Alaska SeaLife Center for necropsies. Additionally, one fresh Common murre ( Uria aalge )
carcass was recovered. Six of the mortalities (1 eider, 5 Harlequi n duck) were likely killed or scavenged by eagles.

Contaminants, Health, and Virus samples

All blood and cloacal samples we re sent to Dr. Tuula Hollmén (Alaska SeaLife Center) for analyses (Table 3).
Table 3. Summary of blood and cloacal samples collected at Dutch Harbor 2004.

Species Serum Whole Blood Virus Swab Fecal Sample

Steller’s eider 25 17 27 25 Harlequin 38 28 19 17 Black scoter 2 0 1 5 White-winged scoter 7 6 2 4 Long-tailed duck 2 1 1 1 Table 2. Telemetry effort and detection success from locations around Dutch Harbor 2004.
Telemetry Search Area Airport Beach 1 Sewage Outflow Inner Harbor Mid Captain’s Bay 2 South Captain’s Bay # Telemetry searches 246 80 38 167 111 # Detections Steller’s eider 2485 511 221 1946 678 Harlequin duck 2794 585 266 1273 894 # Definite Locations Steller’s eider 889 189 58 841 292 Harlequin duck 869 100 83 330 553

# Triangulation searches 90 35 - 78 75 # Triangulation fixes Steller’s eider 170 3 - 225 68 Harlequin duck 260 6 - 83 142

1 includes birds near Hog Island 2 includes South Eastern edge of Little South AmericaWintering Steller’s Eiders at Dutch Harbor 7



### DISCUSSION

Capture Success

Our 88 total captures compares well to capture su ccess in previous years at Dutch Harbor. Conditions during the capture period in 2004 favor ed our success. We had several days with sunny weather and stiff southerly breezes that worked well for the floating mist net set. Additionally, the Steller’s eider floc ks tended to be smaller in size than some years, consequently our decoy spreads proved to be more attractive to small groups of birds looking for locations to
settle.

Site Fidelity, choice, and Movement

For several birds, detection was intermittent, i.e., ‘present’ one day, absent the second, and then ‘re-appeared’ several days later. These birds ma y have made daily movements to areas outside our range of reception. Concentrations of radi o-marked Steller’s eiders and Harlequin ducks were consistently heard and seen in three main areas: 1) along the Air port Beach (between the runway and the Post Office), 2) Hog Island, and 3) Little South America. Harlequin ducks also used the south end of Captain’s Ba y, while only a few Steller’s eiders were detected in this area. We observed that a few times per day the sewage outflow area was visited for short periods (<1 hr) by large numbers of sea ducks. All but four of the radio-ma rked Steller’s eiders and twothirds of the Harlequin ducks were detect ed around the sewage outflow area on multiple
occasions.

As we have seen in previous years of teleme try, wintering Steller’s ei der and Harlequin ducks showed fairly strong site fidelity. Most birds were continually detected near their original banding site. However, we did detect a substa ntial amount of movement, both daily and through the sampling period. By and large, Steller’s eide rs had larger home ranges than Harlequin ducks and were more likely to make large-scale (>3 km) movements. It a ppears that many ducks concentrated at night near the runway, Hog Island, a nd Little South America and then dispersed at sunrise. During periods of strong winds (e sp., North winds) ducks con centrated in protected areas near the airport and Little South America. For short periods each day many ducks gathered to feed in the sewage outflow area and then during low tide hauled out to preen on the pointsWintering Steller’s Eiders at Dutch Harbor 8



### near the entrance to Captain’s Bay and at the west end of Airport Beach (n ear the Post Office). Results from radio tracking in 2001 and 2002 indi cated that birds routin ely moved between the Little South America, th e ‘Inner Harbor’ (at the mouth of the Iliuliuk River), and southwestern Iliuliuk Bay (In front of Unalaska proper). By contrast, in 2004 only a few of our radio-marked
birds used the Inner Harbor and none were detected by Iliuliuk Bay.

For further information contact:
US Geological Survey Alaska Biological Science Center 1011 East Tudor Road Anchorage, Alaska 99503

Paul L Flint 907-786-3608 Paul_flint@usgs.gov

John Reed 907-786-3485 John_Reed@usgs.gov



### Literature Cited
Dachs, J., Eisenreich, S.J., and Hoff, R.M. 2000. Influence of eutrophication on air-water exchange, vertical fluxes, and phytoplankton concentrations of persistent organic pollutants. Environmental Science and Technology. 34:1095-1102.
Flint, P.L., Petersen, M.R., Dau, C.P., Hines, J.E., and Nichols, J.D. 2000. Annual survival and site fidelity of Steller’s eiders molting al ong the Alaska Peninsula. Journal of Wildlife Management. 64 (1): 261-268.
Fox, A.D., Mitchell, C., Henriksen, G., Lund, E. , and Frantzen, B. 1997. The conservation of Steller’s eider Polysticta stelleri in Varangerford, Finnmark, Norway. Wildfowl. 48: 156-165.
Gunnarsson, J., Bjork, M. Gilek, M., Grankbe rg, M., and Rosenberg, R. 2000. Effects of eutrophication on contaminant cycling in mari ne benthic systems. Ambio. 29(4-5):252- 259.
Hoffman, C. COE 2000. Unalaska Trip Report, St eller’s Eider Survey No. 1 for December 2000. Memorandum for record. CEPOA-EN-CW-ER. U. S. Army Corps of Engineers, Alaska District, Anchorage.Wintering Steller’s Eiders at Dutch Harbor 9



### Hoffman, C. COE 2001. Unalaska Trip Report, Ste ller’s Eider Survey Nos. 1-3 for January - March 2001. Memorandum for record. CE POA-EN-CW-ER. U.S. Army Corps of Engineers, Alaska District, Anchorage.
Pietz, P. J., D. A. Brandt, G. L. Krapu, and D. A. Buhl. 1995. Modified transmitter attachment for adult ducks. J. Field Ornithol. 66:408-417.
Persson, J., Axelman, J., and Broman, D. 2000. Validating possible eff ects of eutrophication using PCB concentrations in bivalves and se diment of the US mussel watch and benthic programs. Ambio. 29 (4-5): 246-251.
Skei, J., Larsson, P., Rosenberg, R., J onsson, P., Olsson, M., and Broman, D. 2000. Eutrophication and contaminants in aqua tic ecosystems. Ambio. 29 (4-5): 184-194.