AUKE BAY LABORATORY (ABL) (cont.)

Migration of Pink Salmon Fry From Auke Lake in March 2003

Figure 1. Number and timing of pink salmon fry migrating from Auke Lake in 2003.

Large numbers of Auke Lake pink salmon fry moved downstream to Auke Bay in March 2003 (Fig. 1), the second highest number of March migrants recorded in 30 years; only 1984 had higher numbers following the strongest El Niño (1983) recorded in recent years. El Niño conditions have been present in the tropical eastern Pacific during the past year but may be weakening at present. Winter conditions in Southeast Alaska were mild during 2002-03 with above average air and water temperatures. Such conditions can be associated with El Niño conditions in the tropics and may explain the high numbers of early migrants. No major plankton bloom has yet occurred in Auke Bay during spring 2003, so available food organisms for these early fry may be sparse.

By Jerry Taylor and John Karinen.

Environmental Monitoring in Auke Bay

Temperature and weather data recorded at the ABL station indicated milder than normal weather in Southeast Alaska for fall and winter 2002-03. Ocean surface temperatures were slightly below average in October. Mild weather resulted in surface temperatures being 1.2°C above average in November and slightly above average in December. Ocean surface temperatures dropped a bit below average in January 2003, but returned to 1.2°-1.4° above average in February and March.

Precipitation was above average in October, November, January, and March, and below average in December and February. Snowfall was well below average for the whole season as a result of the generally warmer than average air temperatures.

By Bruce Wing.

NMFS Aquaculture Council

The NMFS Aquaculture Council met on 22-24 January 2003 at the NMFS Galveston Laboratory in Texas. Fourteen council members attended, representing most NMFS Headquarters Offices and several Science Centers and Regions. Two main issues were considered: 1) development of responses to public comments received by the agency to a notice published in the Federal Register concerning a Draft Code of Conduct for Responsible Aquaculture Development in the U.S. Exclusive Economic Zone (EEZ), and 2) rewording of draft legislation for a new National Marine Aquaculture Act consistent with objectives and provisions of the National Aquaculture Act of 1980 (as amended). The principal focus of the new legislation is to address many of the issues around development of marine aquaculture in offshore waters in the U.S. EEZ, including provisions for the leasing of sites for aquaculture use.

By Bill Heard.

Sea Lice Science Forum

The University of British Columbia and the Science Council of British Columbia hosted a Science Forum on Sea Lice on 22-24 February 2003.  The purpose of the forum was to review available science on the interactions of sea lice and farmed salmon and on the potential impacts of sea lice on wild salmonids.

The forum was held partly in response to the highly polarized and controversial debate over the role and potential impacts of the salmon farming industry on marine ecosystems in British Columbia. Another key event leading up to the forum was a dramatic decline in adult pink salmon returns in 2002 to the Broughton Archipelago region in central British Columbia. This area has concentrations of salmon farms where heavy sea lice infestations on juvenile pink salmon were documented as the salmon migrated seaward in 2001. This potential cause and effect scenario was viewed by many as evidence that sea lice originating from the farms were the principal cause of the decline of pink salmon returns in 2002.

A total of 26 invited speakers participated in the forum, including many speakers from Europe—primarily Norway, Scotland, and Ireland—where there is a long history of sea lice issues associated with salmon farming.  ABL scientist Bill Heard was asked to address the forum and review aspects of pink salmon population dynamics, especially related to potentially high density-dependent freshwater mortality caused by excess escapements of spawning salmon.

 In 2000, the parent year of the 2002 returns, pink salmon spawners returned to the Broughton region in record high numbers, suggesting an alternate hypothesis that the record escapements led to unusually low numbers of surviving fry that migrated from freshwater in 2001. Unfortunately, there is little relevant field data on this issue beyond the documentation of unusually large escapements to the area in 2000.

Past research, however, has documented that overseeding of spawning gravels with too many eggs causes high density-dependent mortalities of eggs and alevins in pink salmon, especially during critical periods when high biochemical oxygen demands and oxygen privation cause heavy mortalities during the midwinter period. There is little doubt that the sea lice infestation on juvenile pink salmon in 2001 was detrimental to adult returns the following year, although there is also considerable doubt that sea lice infestations were the principal cause of that decline.

The forum concluded by identifying high priority research needed to more fully understand the role of salmon farms, of sea lice, and of their potential impacts on wild salmon populations, along with the need for collecting more population dynamics data on wild salmon stocks. The Canadian Ministry for Agriculture, Food and Fisheries announced at the forum the commitment of almost $1.0 million to immediately begin addressing these research needs. A position paper will be forthcoming that details findings of the science forum.

By Bill Heard.

Scientists Receive Environmental Health and Safety (EHS) Training

Scientists from ABL’s Marine Salmon Investigations and Habitat Programs attended the 2003 Laboratory Safety and Environmental Management Conference held in Februrary in Alexandria, Virginia. The conference was cosponsored by Prizm Inc. and the National Pollution Prevention Roundtable. A preconference training course titled “What EHS Managers Need to Know about Green Laboratory Design” focused on reducing energy waste through sustainable design or cost-effective upgrades. It also focused on reducing laboratory energy consumption while maintaining or improving safety, environmental performance, and occupant health.

The conference itself addressed topics including laboratory ventilation and a safe research environment, preparing for emergency responses, ergonomics in the laboratory, compliance in academic laboratories, bio-safety risk assessment and management, implementing management systems, animals in labs, the one-person EHS department, hazard reduction in the laboratory, pollution prevention and sustainable development, chemical safety and public policy, laboratory energy efficiency for the 21st century, and a forum on laboratory EHS.  

A postconference training course  “Pro-active Laboratory Chemical Management” reviewed laboratory chemical storage practices and how to minimize problems with chemical incompatibility.  In addition to various training and conference seminars, interaction with scientists and safety officers from various private, government, and academic institutions provided extra information on safety matters and regulations not covered in the conference.

By Andy Gray.

AFSC Quarterly
Research Reports
Jan-Feb-Mar 2003