Fry 



Chapter 25 



Pollution and Fishing Threats 



similar to that of murrelets, indicating that murrelets could be 

 at risk from pulp mill effluents. 



The discharges from the mills have generally been 

 localized to the vicinity of less than 25 km from the mill 

 (Colodey and Wells 1992), with variable local impact on 

 wildlife populations. Since pulp mills and Marbled Murrelets 

 are both distributed all along the Pacific coast, the discharges 

 from these mills is of concern. 



The mills most probably affecting murrelets would be 

 those in southeast Alaska, British Columbia, Washington 

 (Port Angeles, Bellingham, Everett and Grays Harbor), and 

 California (Eureka). The distribution of murrelets in 

 Washington is primarily in the Straits of Juan de Fuca and in 

 the San Juan Islands (Speich and others 1992), with fewer 

 birds in the more polluted areas of southern Puget Sound. 



The high toxicity and very long environmental persistence 

 of dioxins and furans has resulted in regulatory action reducing 

 pulp mill effluent discharges, and is also resulting in changes 

 in the bleaching processes used by paper-grade pulp mills to 

 eliminate chlorine bleaches. Most mills in the United States 

 and Canada continue to use chlorine bleaches, but effluent 

 discharges in British Columbia were reduced by 75 percent 

 between 1989 and 1991 (from 81.5 to 20.5 metric tons of 

 chlorinated organics per day). It had been determined that 

 most mills will retool to convert to oxygen bleaches or close 

 down (Colodey and Wells 1992). The Ocean Falls mill in 

 British Columbia closed in 1981, but persistent residues may 

 still affect the population of murrelets using adjacent fjords 

 (Burns and Prestash 1993, Manley and Kelson 1992). 



Industrial Pollutant Discharges 



Industrial discharges from the population centers of San 

 Francisco Bay, California, Puget Sound, Washington, and 

 Vancouver, British Columbia, have contaminated estuarine 

 sediments with heavy metals, petroleum hydrocarbons, and 

 PCB in addition to PCDD and PCDF (Henny and others 

 1990, Hoffman and others 1986, Ohlendorf and Marois 1991, 

 Phillips and Spies 1988, Riley and others 1983, Speich and 

 others 1988). Marbled Murrelets may be only peripherally at 

 risk, however. Their range is primarily in coastal areas, 

 largely remote from populated areas, because historic logging 

 near population centers has reduced nesting habitats. Pollutant 

 monitoring of Pigeon Guillemots (Cepphus columbd) in 

 Washington indicated that birds resident in the Straits of 

 Juan de Fuca were less contaminated than those resident 

 near Seattle, presumably because contaminated forage fish 

 do not move widely throughout Puget Sound (Calambokidis 

 and others 1985). Murrelet risk would be expected to be 

 broadly similar to the risk to guillemots. 



Non-Point Discharges 



Discharges from Rivers 



The major rivers with historic pollutant discharges in 

 the murrelet range are the Sacramento-San Joaquin 



(California), Columbia (Oregon, Washington), and Fraser 

 (British Columbia). The Copper River, in Alaska, was a 

 source of mining discharge, but probably not currently a risk 

 factor for murrelets. Most other rivers within the murrelet 

 range have little agriculture, or mining pollutant inputs which 

 would affect murrelets. 



The current distribution of murrelets at the mouths of 

 these rivers is generally low, probably because they are 

 human population centers where there has been a historic 

 reduction of murrelet nesting habitat. 



Global Bioaccumulation of 

 Organochlorines in the Food Web 



Murrelets are probably at low risk from global food 

 web bioaccumulation of pollutants because of their foraging 

 habits, prey size and the distribution of prey in coastal 

 habitats. Most fish eaten by murrelets are juveniles of 

 commercial species, or ground fish without a wide pelagic 

 distribution. The background global organochlorine input 

 into the seabirds of the North Pacific has resulted in a 

 modest increase in organochlorine pollutants in seabird eggs 

 over the past two decades (Elliott and others 1989), but the 

 levels remain below those generally considered to be of 

 threshold biological significance. 



Plastics and Small Floating 

 Marine Debris 



Ingestion of floating bits of plastic, rubber filaments, 

 and fishing line has been documented in many seabirds, most 

 commonly in species preying on plankton. Day and others 

 (1982, 1985) documented plastic ingestion by 50 species, 

 including eight species of alcids: Cassin's (Ptychoramphus 

 aleuticus), Least (Aethia pusilla), Parakeet (Cyclorrhynchus 

 psittacula), and Rhinoceros (Cerorhinca monocerata) auklets; 

 Dovekie (Alle alle); Common Murre (Uria aalge); and Tufted 

 (Fratercula cirrhata) and Horned (Fratercula corniculata) 

 puffins. Day (1980) also examined 61 Marbled Murrelets, 16 

 Ancient Murrelets (Synthliboramphus antiquus), 5 Kittlitz's 

 Murrelets (Brachyramphus brevirostris) and 18 Pigeon 

 Guillemots and found no plastic or other foreign objects 

 present in their upper digestive tracts. The lower risk to 

 murrelets and guillemots is probably due to a combination 

 of their coastal foraging and a diet restricted to fish, 

 thereby reducing the likelihood of inadvertent ingestion 

 of foreign objects. 



Oil Pollution Threats 



Documentation of oil spills along the Pacific coast since 

 1968 have demonstrated significant threats to seabirds in 

 California, Oregon, Washington, British Columbia, and Alaska 

 (see also Carter and Kuletz, this volume). Small numbers of 

 murrelets (fewer than 10 birds) were recovered oiled after 

 spills from the tankers Blue Magpie, Oregon, 1983; Puerto 



258 



USDA Forest Service Gen. Tech. Rep. PSW-152. 1995. 



