Changing Our Thinking

Fisheries and Aquatic Ecological Studies

The knowledge acquired from basic fishery population, habitat, and aquatic ecological studies is essential for understanding ecosystem processes and for informing a host of environmental impact assessment, regulations, and natural resource management needs.  Martin Environmental has expertise and broad experience in performing and publishing aquatic ecological studies.  Our services include:
         Fish distribution and abundance surveys
         Fish feeding and food resource studies
         Fish movement and passage surveys
         Habitat inventory and mapping
         Limiting factors analysis
         Stream channel morphology and habitat forming process studies
         Remote sensing and mapping of riparian and stream resources
         Riparian resource inventory

Selected Projects

Core Areas: A Conceptual Framework for the Spatial Structure of Salmon Populations in Rivers

Client: King County, Water & Land Resources Division

Period: 2002 2003

Summary: Understanding the spatial structure of salmonid populations is limited by our knowledge of what mechanisms form spatial structure and how structure affects variations in population survival and abundance. To improve our knowledge, Martin Environmental collaborated with Earth Systems Institute to investigate how spatial structure is formed in salmon populations through a synthesis and analysis of existing information and data from selected Puget Sound rivers. Based on our findings, we proposed a conceptual framework to help understand spatial structure at the population/river basin scale. We also compared the predicted spatial organization of riverine habitats to the actual distribution of spawning habitats for Chinook salmon. Given our results, we proposed there are certain habitats (i.e., core areas) that functionally control population spatial structure, and we describe the key criteria necessary to identify core areas. We believe this information is critical for informing management decisions and for planning restoration measures concerning the conservation of salmon populations.

Patterns of Instream Wood Recruitment and Transport at the Watershed Scale

Client: Sealaska and Alaska Department of Natural Resources

Period: 1999 2000

Summary: Numerous studies have documented the positive role that large woody debris (LWD) plays in riverine ecosystems yet there is limited knowledge of wood recruitment rate and the spatial and temporal controls on LWD abundance and distribution. Understanding the spatial patterns of LWD abundance across a channel network should increase our understanding of fluvial geomorphic and ecologic patterns, including spatial controls on the abundance and diversity of aquatic habitats.  Martin Environmental lead an investigation that collected data on piece size, jam spacing, and jam age for a sixth-order river basin in Southeast Alaska. In collaboration with another scientist (Lee Benda and Associates), Martin Environmental and Benda Associates estimated wood recruitment rates by different input processes, identified spatial controls on wood recruitment, wood transport distances, and spatial patterns of wood abundance.  The LWD budget provided a watershed context for resource management that is useful for determining how and where to protect LWD sources for streams.

Rainbow Trout Population in Black Bear Lake

Client: Alaska Power and Telephone Company

Period: 1997 1999

Summary: The effects of water level drawdown, for hydropower operations, on the viability of a rainbow trout population in Back Bear Lake, Prince of Wales Island, Alaska was investigated over six years. Annual surveys (snorkel, hydroacoustic, and net gear) were performed to determine fish abundance, size, and age composition. Martin Environmental in collaboration with Romey Associates conducted the last two surveys, performed a comprehensive analysis of all data, and prepared a final project report.  The study results were use to support the Federal Energy Regulatory Commission licensing process of the hydroelectric project. 

Distribution and seasonal abundance of juvenile salmon and other fishes in the Yukon River Delta

Client: National Oceanic and Atmospheric Administration (NOAA)

Period: 1985 1986

Summary: The Yukon River Delta supports a large and diverse assemblage of fish species and aquatic habitats that were little studied prior to this investigation. Pending future oil and gas resource development in the region, NOAA  needed baseline information to determine the vulnerability of aquatic resource in the Yukon Delta to the potential impacts of an oil spill.  Dr. Douglas Martin (Martin Environmental) lead an interdisciplinary science team that documented the fish species composition, relative abundance, distribution, and habitat use in the riverine and nearshore waters of the Yukon Delta. The research included an assessment of salmonid fish prey resources, food habitats, and growth rate. Research methodology involved combining data from satellite imagery with oceanographic data to identify habitat characteristics and spatial patterns.     

Factors Affecting Pink Salmon Pre‑spawning Mortality in Southeast Alaska

Client: Tongass National Forest and Alaska Timber Industry

Period: 1990

Summary: The environmental factors and basin characteristics that produce lethal conditions and cause pre-spawner mortality of adult salmon is not well known.  Periodic fish kills in Southeast Alaska had previously been attributed to high stream temperature, low dissolved oxygen (DO), and low stream flows in summer. To investigate this problem, a consortium of resource managers and agency scientists contracted Dr. Martin (Martin Environmental) to perform a field investigation of the suspected causal factors for pre-spawner mortality.  Water temperature, DO, and other physical factors were monitoring during salmon migrations in streams with different geomorphic characteristics. Dissolved oxygen was found to be the key factor driving mortality and sensitivity analysis was used to identify the relative importance of environmental factors affecting DO concentration in streams during the migration period. The study identified factors that made streams susceptible to fish kills and how these may relate to resource management.      

Entrainment of Juvenile Salmonids into Hydropower/Irrigation Canals of the Yakima River During Winter

Client: Bonneville Power Administration and Yakima Indian Nation

Period: 1985

Summary: Screening of irrigation diversion canals is an effective method to prevent entrainment and mortality of juveniles salmonids. The need for screening during the winter months however had not been studied because fish movement was assumed to be limited. To address this issue, BPA contracted with Dr. Martin (Martin Environmental) to assess the magnitude of entrainment of juvenile salmonids and to identify environmental factor that could account for the timing and magnitude of fish movements. This study found that entrainment was a significant concern during winter and provided valuable information that helped the Bureau of Reclamation to implement protective measures.