1.1.1.1 Examples of Answers to Basic Status and Trend Questions

Oregon Coast Coho Spawner Monitoring ...click here

Hugh Smith Lake (Alaska) Sockeye Monitoring ...click here 

Answers to Basic Status and Trend Questions for Oregon Coast Coho Spawner Monitoring

A) What information is needed?

Indicator(s):

• Abundance of natural origin spawners
• Distribution of natural origin spawners

Species:

• Coho (Oncorhynchus kisutch)

Life stage(s):

• Spawners

B) Who needs the information:

Audience(s):

• Public
• NOAA Fisheries
• State and federal legislators
• Oregon Fish and Wildlife Commission
• Pacific Fishery Management Council
• Oregon Watershed Enhancement Board
• Watershed councils
• State and federal natural resource management agencies
• Oregon Department of Fish and Wildlife managers and scientists

C) Why is the information needed?

Reason(s): 

• The information is needed to assess the status and trend of coho salmon populations in the Oregon Coast Coho Evolutionarily Significant Unit (ESU).  Oregon coast coho are currently listed as threatened under the U.S. Endangered Species Act.  Information on the current abundance and trend in abundance are key components of assessing progress towards recovery goals established for these fish.  The information is also used in the process of estimating allowable incidental harvest mortalities associated with ocean troll fisheries for other species and hatchery coho.

D) How well do you need to know the information? 

Degree of certainty:

• Estimates of abundance with 95% confidence intervals of +- 30%
• Ability to detect a 30% change in the annual distribution of natural origin coho

E) When is the information needed?

Total time span:

• Ongoing - no anticipated end for discontinuing reporting on indicators

Reporting Intervals:

• Annual.

F) Where is the information needed?

Total geographic extent:

• Oregon Coast Coho Evolutionarily Significant Unit (ESU) ...click here

Discrete spatial scales: 

• Four Oregon Coast Coho Monitoring Areas ...click here
• 21 Oregon Coast Coho Independent Population Areas ...click here
• Oregon Coast Coho Dependent Populations Grouped by Four Monitoring Areas ...click here

G) What is/are your target statistical population(s)?

Target statistical population(s): 

• All areas in all streams in the Oregon Coast Coho ESU with habitat suitable coho spawning habitat.

H) What metrics will you use to develop your indicators and how often during the reporting interval must data be collected for them?

Metrics:

• Area-under-the-curve estimates of the number of live fish occuring at survey sites over the course of the spawning season. 
•  The percentage of all carcasses observed during spawning surveys that are of hatchery origin

Metric time intervals: 

• Both metrics are calculated once each spawning year

I) What is known about the variability of your metrics?

Observer error information:  

• Solazzi, M.F. 1984. Relationship between visual counts of coho, chinook and chum salmon from spawning fish surveys and the actual number of fish present. Oregon Department of Fish and Wildlife, Information Reports (Fish) 84-7, Portland....click here
• Jacobs S., 2002. Calibration of estimates of coho spawner abundance in the Smith River basin, 2001; Monitoring Program Report Number OPSW-ODFW-2002-06, Oregon Department of Fish and Wildlife, Portland, Oregon. ...click here 

Spatial variability information:

Enlarge Image

Temporal variability information:

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Note in figures above that 1998-99 were low abundance years and 2001-2003 were high years

 

Much of the annual variability shown above is due to variability in ocean survival (see below)

Enlarge Image

Site-by-year variability:  No empirical data available.

J) What constraints are associated with accessing sample sites within your statistical population?

Site access constraints: 

• A small proportion of potential spawning sites located on private land will have access denied.  This denial of access is should generally be below 10%.  
• To reduce cost of implementing new program, if possible new surveys should mesh with existing survey reaches. 

K) What constraints do you have in collecting data at different times?

Temporal constraints: 

• Winter storms can make it dangerous for survery crews to attempt to access sites at certain times.  Past experience has shown that these inclement conditions usually do not exceed 10 day, which is the maximum allowable time interval between observation periods at a site.

L) What constraints are associated with developing your metrics or collecting data for them?

Metric constraints:

• Must be able to access spawning sites at least once every 10 days throughout the spawning season
• During each 10 day interval, stream flows must be low enough and water clear enough to allow for visual counts of live adult coho over spawning redds
• Must be able to distinguish between natural and hatchery origin coho carcasses found on spawning grounds

M) Funding constraints:

Funding constraints:

• Approximate budget for surveys is roughly $600,000/year.  Approximate cost of surveying a mile of stream for spawning coho every 10 days throught the spawning season is is $1,000.

Answers to Basic Status and Trend Questions for Hugh Smith Lake Sockeye Spawner Monitoring

A) What information is needed?

Indicator(s):

• Abundance of natural origin spawners
• Distribution of natural origin spawners

Species:

• Sockeye (Oncorhynchus nerka)

Life stage(s):

• Spawners

B) Who needs the information:

Audience(s):

• Public
• Alaskan (ADF&G) fishery managers and scientists
• The Alaska Board of Fisheries 
• Affected fishermen

C) Why is the information needed?

Reason(s): 

• In 2003, the Alaska Board of Fisheries classified Hugh Smith Lake as a management stock of concern because of a long history of stock decline and escapement levels far below the published escapement goals. The Board of Fisheries approved an action plan, which changed the management of District 101 purse seine and drift gillnet fisheries. Additionally, the plan called for some level of hatchery stocking. Prior to the stocking, there may have been two distinct sub-populations in the lake, separated because of rearing temperature. The eggs used for the stocking were derived from Buschmann Creek, but a very high proportion of the adult spawners in Cobb Creek showed otolith marks identifying these fish as hatchery derived. Although the stocked fish had a high survival back to the lake, the stocked fish had a low rate of success actually breeding. Because of the very intense fisheries in the of Hugh Smith Lake, the adult escapement should be monitored annually.

D) How well do you need to know the information? 

Degree of certainty:

• Estimates of sampling error are not used in this assessment. Fish are counted through a counting weir, one by one. However, a small sample of fish are marked, and a relatively low-precision mark-recapture study is used to detect a weir failure, if one should occur.

E) When is the information needed?

Total time span:

• Weekly escapement information is used in actual in-season management
• Annual information is used to judge management effectiveness
• The Alaska Board of Fisheries reviews the status of this stock every three years 

F) Where is the information needed?

Total geographic extent:

• The two spawning aggregations within Hugh Smith Lake: Buschmann Creek and Cobb Creek

G) What is/are your target statistical population(s)?

Target statistical population(s): 

• The adult breeding population within Hugh Smith Lake

H) What metrics will you use to develop your indicators and how often during the reporting interval must data be collected for them?

Metrics:

• Actual weir counts of adult salmon.
• A mark-recapture estimate of fish passing by the weir, which is used to detect an unobserved failure of the weir's integrity.

Metric time intervals: 

• Weir counts are reported daily, weekly, and seasonally.
• The mark-recapture estimate is reported seasonally.

I) What is known about the variability of your metrics?

• The weir count and the mark-recapture estimates at Hugh Smith Lake have traditionally had near perfect correspondence, leading to high confidence in the weir counts.

See Geiger, H.J., T.P. Zadina, and S.C. Heinl. 2003. Sockeye salmon stock status and escapement goals for Hugh Smith Lake in Southeast Alaska. Regional Information Report 1J03-05. Alaska Department of Fish and Game, Division of Commercial Fisheries. Juneau, Alaska.

Site-by-year variability:  No empirical data available.

J) What constraints are associated with accessing sample sites within your statistical population?

Site access constraints: 

• Hugh Smith Lake is located in a remote section of Alaskan wilderness.  

K) What constraints do you have in collecting data at different times?

Temporal constraints: 

• Because a stream weir requires daily monitoring, this project requires full-time staffing during the data-collection period.

L) What constraints are associated with developing your metrics or collecting data for them?

Metric constraints:

• The weir must be installed, fish tight, and well maintained during the entire spawning migration into the lake.
• The project must be staffed during the entire spawning migration.

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