Jump to content

Draft Addendum IV

Rate this topic


cbh75

Recommended Posts

I had the following exchange with RJ this week that he correctly suggested should be in the forum.  Anyone have any thoughts as we head into the NJ public meetings?


Hi RJ,

I've been reading the Draft Addendum IV in advance of the Toms Rivererting on 9/15 and have a question that you'll probably know the answer to. Here it is: the proposed options B2 (1@30); B3 (1@32); and B4 (1@28-40) all reduce harvest by 31% or more but how do these relate to Ssb? We always hear that we should let the big girls go and it doesn't seem that raising the minimum size without a cap does anything more than make sure bigger fish get killed. Should the focus be on protecting more 28-30 inch fish, or in protecting the big girls folks always talk about...or am I mixing apples and oranges?



 

RJ's Response:

 


One at 32" or larger B3 would be my preference. The female population is in the majority. 1 fish limit will reduce overall harvest by 31% as you stated. B4 would harves a larger percentage of the 28 to 30 inch striped bass. That population range is more numerous and there for subjected to higher harvest numbers, thus reducing the number of mature Age 8+ females that could spawn once before being harvested.

cbh75. The next time you have a question, please post it on the forum rather than the PM. Your question is excellent ans I hope my answer is as well. Only you and I benefit from the information shared experience. There are a lot of interested parties on the forums who would benefit or argue pros and cons on your question and my answer.

I believe the SSB numbers are falling due to lack of recruitment because the Chesapeake Bay female numbers have been bearing the brunt of the Mycobactiosis is causing increases in

natural mortality and the increase in recreational harvest percentages since 1997. The combination of great leaps in striped bass anglers in the past 25 years and the expanding percentage of Chesapeake Bay YOY year counts being ravaged by Myco.

B5.4.8 Natural Mortality and Disease (ASMFC Striped Bass) 2013 ASSESSMENT

The epizootic of mycobactiosis was first detected in the Chesapeake Bay in 1997 (Eckert et al

2001; Rhodes et al. 2001). However, a retrospective examination of archived tissue samples by Jacobs et al. (2009a) suggested that mycobacteriosis was apparent in Chesapeake Bay striped bass as early as 1984. A rise in Mycobacterium disease in Chesapeake Bay could be causing increases in natural mortality (Pieper 2006; Ottinger and Jacobs 2006). Two primary hypotheses have emerged regarding the mechanism for increased natural mortality (Vogelbein et al. 2006).

One is that elevated nutrient inputs to the Bay, with associated eutrophication, results in loss of thermal refuges for striped bass, forcing them into suboptimal and stressful habitat during the summer.

A second is that alternations in trophic structure and starvation have resulted due to over-harvest of key prey species such as Atlantic menhaden (Brevoortia tyrannus) and reductions in the forage base in Chesapeake Bay.

Prevalence of the disease ranges from ~50% as determined through standard histological methods. (Overton et al. 2003), to up 75% with molecular techniques (Kaattari et al. 2005).

Prevalence is dependent on the age class sampled with prevalence increasing with age to approximately age 5 and then decreasing in older ages (Kaattari et al. 2005; Gauthier et al. 2008).

The decline in prevalence with older ages is likely due to increased mortality in fish which have contracted the disease and do not live to older ages as there appears to be limited ability of striped bass to resolve the disease once it is contracted (Matt Smith, unpublished data).

RJ

Life may be sweeter, for this I don't know...

Link to comment
Share on other sites

Create an account or sign in to comment

You need to register here in order to participate.

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...