Tag Archives: abundance estimates

Babine River Sockeye Migration and Predation Assessment

Lake Babine Nation Fisheries (LBNF) plans to work with Fisheries and Oceans Canada (DFO) to continue the investigation of the behaviour and ecology of Babine River sockeye fry. The proposed project is composed of four relatively discrete components which include:

  1. early life history behaviour and migration;
  2. extent and rate of predation on juvenile sockeye;
  3. egg-to-fry and fry-to-smolt survival, frequency of occurrence of disease and parasites and condition as a function of length and weight; and
  4. presence and behaviour of sockeye fry rearing in downstream slow water habitats to obtain evidence of a riverine juvenile sockeye ecotype.

Other observed adverse effects that may affect sockeye fry survival and overall sockeye production will be documented. These studies are intended to address the diminished abundance of Late Run Upper and Lower Babine River sockeye in their juvenile freshwater environment.

 

 

Boundary Area Coho Escapement

The Hugh Smith Lake coho salmon population is substantially exploited by mixed-stock fisheries in both the U.S. and Canada and is, therefore, a key indicator stock used to monitor total adult abundance and escapements, and the pattern and intensity of exploitation by these fisheries on populations in the northern boundary area. It is the only system in the southern portion of Southeast Alaska where a total count (with back-up mark-recapture estimate) of coho salmon escapement has been routinely collected since 1982. Its location 70 km southeast of Ketchikan makes it a particularly strategic indicator stock for boundary area fisheries. It has also been one of three key indicator stocks used to measure the overall abundance of wild coho salmon available to the Alaska troll fishery and to measure the exploitation rate by the fishery.
Escapement projections are made from both the cumulative weir count and estimation models based on recovery of coded-wire tags to provide real-time information for management of fisheries for escapement. Peak helicopter survey counts at other Boundary Area streams provide an index with greater coverage that complements higher resolution assessment at Hugh Smith Lake.

 

Hugh Smith Lake Coho Smolt Enumeration and Marking

The Hugh Smith Lake coho salmon population is substantially exploited by mixed-stock fisheries in both the U.S. and Canada and is, therefore, a key indicator stock used to monitor total adult abundance and escapements, and the pattern and intensity of exploitation by these fisheries on populations in the northern Boundary Area. Its location 70 km southeast of Ketchikan makes it a particularly strategic indicator stock for boundary area fisheries. It has also been one of three key coded-wire tagged indicator stocks used to measure the exploitation rate by the Alaska troll fishery and to estimate the overall abundance of wild coho salmon available to the fishery. Timely escapement projections are made from both the cumulative weir count and estimation models based on recovery of coded-wire tags to provide real-time information for management of fisheries for escapement goals.
The Hugh Smith Lake coho salmon population has been the only long-term, continuously operated wild coho indicator stock project in the northern boundary area, with a record of catch, escapement, smolt production, marine survival, and age composition estimates dating from 1982. The proposal would continue to fund operation of a smolt weir to enumerate and coded-wire tag coho salmon smolts emigrating from Hugh Smith Lake to generate total population estimates, including total smolt production, marine survival, exploitation rate, and catch by area, time, and gear type. Coho smolt estimates and tag recovery rates in the Southeast Alaska troll fishery will be used to generate inseason estimates of marine survival and total adult abundance for fishery management. Estimates of brood year smolt production and adult return by age class will be used to evaluate and refine the biological escapement goal. Counts and samples of sockeye salmon smolts are also obtained at the smolt weir and have been used to evaluate escapement goals and effectiveness of sockeye salmon stock enhancement efforts. The proposed project will continue a core stock assessment program needed to manage fisheries for coho salmon in the northern Boundary Area.

Assessment of an Adaptive Resolution Imaging Sonar (ARIS) for fish counting in the Lower Fraser River

In the 2015 field season, the Pacific Salmon Commission’s Stock Monitoring Group leased an Adaptive Resolution Imaging Sonar (ARIS) system for counting fish passage and estimating behaviour and size distributions of salmon species at its hydroacoustic site on the Fraser River near Mission, B.C. The Southern Fund Committee (SFC) provided funding for this experiment, which demonstrated that the ARIS sonar was able to capture high-resolution images of fish targets allowing users to enumerate salmon passage and fish size at the site. As a new generation of imaging sonar, ARIS inherits many core technological features of the Dual-frequency identification sonar (DIDSON) while providing users with greatly enhanced and superior utilities for various needs, which will provide PSC with more accurate and precise estimates of near-shore salmon passage than the current split-beam system can ever achieve.
Sound Metrics Corporation (SMC), the parent sonar manufacturer of ARIS and DIDSON, has started to gradually phase out DIDSONs from the market. The imaging sonar systems are a very important component of the Mission hydroacosutics program, which have improved the accuracy of salmon-flux estimation in near-shore waters. Given the success of the 2015 pilot lease project noted above, the successful regional adoptions of ARIS for salmon enumeration in Alaska and Washington State, and PSC DIDSON units being beyond the manufacturer’s projected lifespan, we propose to modernize the Mission site and implement the ARIS imaging sonar into our daily estimation for the 2016 field program.

 

Babine Lake Sockeye Smolt Enumeration – Mark-Recapture

The Lake Babine Nation Fisheries Department (LBNF), in collaboration with the DFO, propose to build on success in the smolt project by continuing to operate the Babine smolt enumeration facilities to provide sockeye smolt emigration estimates and smolt fitness data for the Babine Lake Watershed. Smolt production and fitness are effective indicators of Babine Lake ecosystem health which can be used to initiate and direct resource management initiatives intended to protect the Babine Lake watershed. We believe that continuous data from the Babine smolt enumeration fence would provide important information on Babine sockeye population status that will contribute critical information to the understanding the large inter-annual variations in returns observed in the past two decades. An uninterrupted set of sockeye smolt population data over multiple years will help address one of the most fundamental questions of salmon stocks management — under which conditions are freshwater or marine environments the primary driver determining salmon returns?