Reef Fish Monitoring Yellowtail Snapper Survey and Characterization of Tiger Grouper Aggregation Site

 

How is it funded, who administers it?

 

Why was the survey originally designed?

 

    Among the major recommendations made by the participants of SEDAR workshop are the followings:

 

What are/were the intended outcomes/objectives?

 

 

Describe the temporal and spatial coverage of the survey

Show the geographic coverage (including depth) of the survey (maps are helpful)

 

How often is the survey conducted (annually, biennially, biannually etc)?

 

Is it seasonal?

 

Describe the underlying experimental design

Fixed site or stratified-random (If stratified-random, describe the strata)?

 

Describe allocation of sites per strata (proportional/weighted? )

 

Describe the methodology and gear

 

Procedures

Yellowtail Snapper Survey:

Stratify the west and east area in fishing sites and non-fishing sites.  Select randomly 5 non-fishing sites and 10 (if available) fishing sites.

Sample each area four times, one per season.

Sampling will be conducted at night for two hours using hook and line and sardine as bait.

Three lines, each with three hooks, will be used during the sampling.

For each trip the following data will be recorded:

Histology Procedure

As a side study to this project the gonads of the fish caught were collected and preserved for histological analysis. Pictures of the gonads were taken and identified with the gonad information. Upon collection gonads will be weighed, fixed in Davidson’s fixative, embedded in Paraplast, sectioned and stained with hematoxylin and eosin. The slides were examined to determine sex and reproductive stage.  The same categories used for the visual identification were used for female fishes.  It was observed that for males, the reproductive stage were not as discrete as in females, for this reason the categories used were mature (M) or immature (I). The results were compared with the visual classification recorded when processing the fish.  The purpose of this was to create a visual aid for the reproductive stage identification of gonads for the different fish species, and use it as a quality control for the visual identification of the fish gonads.  

The annual reproductive cycle will be described by the monthly distribution of gonadal development stages (GDS) and by the average gonadosomatic index (GSI=100[ovary weight/ ovary weight + somatic weight]) plotted against month of collection for some species that are under evaluation by the Reproduction Program of the FRL. To determine size at maturity (defined as the smallest size class in which 50% of the individuals are sexually mature, L50) a maturity curve will also be developed for those species under consideration by the Reproductive Program.

 

Describe the outputs of the survey

Describe the data outputs & include a discussion of the variance structure of the data

 

Self-Evaluation of pros and cons of survey

What suite of species does this survey target (what are gaps)?

 

What are the gear/method biases (catchability, size selectivity)?

 

What are the temporal/spatial limitations?

 

Is this survey expected to continue into the future?

 

It is relatively expensive/inexpensive, logistically difficult/easy?

 

Self-Evaluation of utility of survey for generating information for stock assessment

Spatial/Temporal coverage

 

Data generated: length frequency, spawning stock biomass, and mortality etc.  

 

Provide any other information that may be relevant to this discussion

N/A

 

Provide most relevant documentation (w/PDFs or hyperlinks if possible)

SEAMAP-C Sampling Protocol Manual

SEDAR 8, Final report to SEAMAP 2012


 

. Sampled stations for yellowtail snapper survey off the west coast of Puerto Rico during 2010-11

Figure 1. Sampled stations for yellowtail snapper survey off the west coast of Puerto Rico during 2010-11.

 

Selected stations off the east coast of Puerto Rico for yellowtail snapper survey

Figure 2. Selected stations off the east coast of Puerto Rico for yellowtail snapper survey.