Left photo:, Myctophids (lampfish). Right photo: Pacific sandfish & pink shrimp.

Map of southeast Alaska with graph of forage species by percent frequency of occurance. (Click for full size images)

Forage species include many vertebrate and invertebrate species that provide food for marine fish, mammals, and birds. These forage species play a vital role in the ecological health of the oceans by supplying nutritional energy to marine predators. This group of species varies greatly in their life history, biology, and ecology, which make them very difficult to study. In southeastern Alaska, over 100 forage species were identified using hydroacoustics, trawls, longlines, seines, and remotely operated vehicles (ROVs).

Hydroacoustics, which use sound waves to detect fish, have been used to enumerate forage species throughout the water column. Hydroacoustics produces an echogram (an acoustic picture) in which dense layers of forage species are detected. Pelagic trawls are then conducted to sample fish from within the dense layers, identify species seen in the echogram, and collect biological data. Longlines are used to collect bottom-dwelling species while seines and ROVs are used to survey close to shore.

Pacific herring (Clupea pallasii) and walleye pollock (Theragra chalcogramma) are two common forage species sampled in our surveys, while bigmouth manefish (Caristius macropus) and longfin dragonfish (Tactostoma macropus) are sampled infrequently. Other forage species include invertebrates, such as shrimp, squid, and jellyfish.

Deep water acoustic echogram.

Contact:
Dave Csepp
Auke Bay Laboratories
Alaska Fisheries Science Center, NOAA Fisheries

Ted Stevens Marine Research Institute
17109 Pt Lena Loop Rd
Juneau AK 99801
Dave.Csepp@noaa.gov

Featured Research, Publications, Posters, Reports, and Activities

• WOMBLE, J. N., M. F. SIGLER, and M. F. WILLSON. 2009. Linking seasonal distribution patterns with prey availability in a central-place forager, the Steller sea lion. J. Biogeogr. 36:1-11 
   
• Lynn Canal Pacific Herring: a Member of One Big Meta-population
  By:  S. WILDES, J. J. VOLLENWEIDER, J. GUYON
  Conference:  Alaska Marine Science Symposium, Anchorage, AK, Jan 2009
  (2009 poster, .pdf, 223KB)   Online.
   
• Tag Retention and Effects of Tagging on Movement of the Giant Red Sea Cucumber
  
  
• Southeast Alaska: Oceanographic Habitats and Linkages
  
  
• The Potential Role of Water-column Stability and Nutrients in Structuring the Zooplankton Community
  
  
• Stock-Structured Distribution of Western Alaska Juvenile Chinook Salmon From United States BASIS Surveys, 2002-07
  
  
• BASIS Symposium Held in Seattle
  
  
• Spatial Distribution, Energetic Status, and Food Habits of Eastern Bering Sea Age-0 Walleye Pollock
  
  

See the publications and poster databases for additional listings.