Pretty good stuff here to add to the DISCUSSION not debate about the mortality rate of Sturgeon and fishing for same. I got this today from a bio within the WDFG. I am truely impressed with the time he took to answer my questions in detail and give me alot of additional information to look at. I won't give his name to keep him from getting punded on remarks, etc... I still got four other documents that he sent to digest, but thought I'd put this out there for you guys to read and form your own bais thoughts. Again, I think alot of folks totally mishandle these great fish, whether by breaking off during a fight and hook remaining within, or grabbing gills and pulling up onto the boat etc... Anyhow here it is with my questions I asked him and his responses. I know one thing, I'm going to switch to circle hooks as I had planned to try in the near future anyhow... Mike
Hello Mike,
I've attached a number of documents that may be of help in answering your
questions. Unfortunately, we do not have any reports that directly address
all of what you are asking about. Why don't you review what I've included,
and, if you have additional questions, get back to me. In the mean time
I've attempted to answer some of your specific questions below.
1) What is the belief within the state of Washington on this (oversize
sturgeon) fishery? And the factors that may limit its future?
. We are confident that the white sturgeon population inhabiting the
lower Columbia River (LCR) is large enough to support both a substantial
keeper fishery and a modest fishery targeting oversize fish. The LCR
population is estimated to exceed 800,000 fish, with 130,000 being of keeper
size. The Fraser River population is estimated to be about 50,000 fish.
. Our management is based on sustainable harvest that takes into
account all sources of mortality (sport and commercial harvest, handling
mortality related to catch and release in sport fisheries and in commercial
fisheries, poaching, and other sources). I would point out that this
sustainable harvest rate will likely have to be reduced in the near future
to compensate for growing losses due to predation by sea lions.
. The intent of our management approach is to escape more fish from
the legal-size population into the broodstock population than are lost from
the broodstock population due to mortality from the various sources.
. The following are links to documents that describe our sturgeon
management approach: LCR Sturgeon Management Implications
(
http://wdfw.wa.gov/fish/whtsturg.htm ), December 9, 2008 Joint State Staff
Report (
http://wdfw.wa.gov/fish/crc/crcindex.htm ).
. We have documented some mortality to broodstock (oversize). After
some initial reports of dead sturgeon washing ashore downstream of the area
where anglers were first starting to target oversize fish in the early
1990s, we became concerned enough to implement a systematic survey of the
Columbia River downstream of the fishery for sturgeon carcasses. Results of
the surveys are provided in the attached "carcass and hook summary". We
suspect that a portion of these fish likely died from being handled in the
sport fishery due to the frequency of ingested hooks found in the carcasses.
As you have hypothesized, these large fish are handled multiple times during
their lifetime, even multiple times in a given year. This is born out in
the carcasses, where we often find multiple hook setups in a fish. Other
indications of hooking-caused mortality include punctured arteries in the
gill area. These impacts would likely be far less if anglers switched from
using J-hooks to using circle hooks.
. We do not know for certain how significant this may be to the
population, partly because we do not know what proportion of broodstock are
lost each year - the unknowns being: 1) the total number of broodstock lost
(we know that only a portion likely wash ashore were we find them) and 2)
the total number of broodstock in the population.
. Because of these concerns, we have implemented a precautionary
approach to managing fisheries that includes protecting broodstock through
instituting spawning sanctuaries - closing certain areas of the river where
sturgeon congregate to spawn during the spawning timeframe.
. This has not eliminated access to oversize sturgeon, only the
portion that we are most concerned about. Anglers still fish for oversize
sturgeon just downstream of the spawning sanctuaries. We have worked with
some of the guides to develop "Best Practices" for fishing for oversize (see
attachment).
2) Is the (B.C.) view different from Washington's as to the
survivability of oversize compared to the taking of keepers for personal
use?
. We have estimated annual survival for legal-size fish but not for
oversize sturgeon, so I cannot compare survival rates between the two
categories. We do believe that an individual broodstock-size fish is much
more valuable to population productivity that a legal or sub-legal size
fish, since the broodstock population is comprised of the very small
proportion of juveniles that ever make it to adulthood.
. I will point out again that we believe that harvest of "keeper"
size fish is supportable as long as it is kept to sustainable levels.
3) Are there actual scientific tests done in Washington that confirm
what is stated (on some web sites) or is it perception?
. I touched on this a bit in the fourth bullet under number 1.
. We have assisted with research on the buildup of stress hormones
in sturgeon handled in the oversize fishery (see the attached Webb report).
The work indicates that the longer it takes to land an oversize sturgeon,
the greater the stress on the fish. One concern we have is that too much
stress at the wrong time may lead to a portion or possible all of a fishes
eggs being reabsorbed. There is nothing definitive on this for white
sturgeon, but it has been documented for some other fish species.
. The best summary of information on the oversize white sturgeon
fishery is contained in the attached "white paper".
4) Nothing is mentioned about contributing factors like grabbing the
gill plates and hoisting them in the boat as shown in several pictures on
various sites. Does the WDF&G have a reward program for people reporting
illegal pulling fish out of the water?
. We rely on our enforcement officers to enforce the rule.
5) Are there thoughts of the fishery becoming C & R?
. The history of our interaction with anglers throughout the
Columbia River indicates strong support from anglers towards maintaining and
enhancing harvest opportunity for white sturgeon. We are able to provide
harvest fisheries in tandem with catch and release opportunity for
sublegal-size, legal-size, and oversize white sturgeon.
6) Is there any way a Joe citizen can be a part of these surveys?
. The stock assessment approach employed on the lower Fraser River
involving the provincial government, paid consultants associated with the
Fraser River Sturgeon Conservation Society, and volunteers has been quite
successful. The limited resources that we currently direct towards managing
the lower Columbia River white sturgeon population are spread between
multiple activities, including sampling fisheries (this takes up most of our
resources), estimating harvest, modeling fishing season scenarios, in-season
fishery management, and stock assessment work including abundance estimation
and tracking other population parameters. Our approach relies on utilizing
staff time from various non-sturgeon programs to help accomplish this. We
have tried to incorporate some public participation with the stock
assessment program, but found that we did not have the resources necessary
to properly oversee such a program to ensure that accurate data was being
collected.
