February 18, 1997

MEMORANDUM TO: Gary C. Matlock
Director
Office of Sustainable Fisheries

FROM:  Patricia A. Montanio
Acting Director
Office of Protected Resources

SUBJECT:  Reinitiated Section 7 Consultation on the Fishery Management
Plan for Commercial and Recreational Salmon Fisheries off the Coasts
of Washington, Oregon, and California as it Affects the Sacramento
River Winter Chinook Salmon


BACKGROUND

On March 8, 1996, NMFS issued a biological opinion that concluded that
the ocean salmon fisheries managed under the Pacific Fishery
Management Council's Ocean Salmon FMP jeopardized the continued
existence of Sacramento River winter chinook.  This opinion is
incorporated by reference.  Since last year's opinion, new information
has become available including an estimate of the 1996 winter chinook
spawning escapement and an estimate of ocean harvest rate on the 1993
brood year.  Based on this new information and additional analysis
described in the Addendum to the 1996 Biological Assessment (see
attachment), NMFS reinitiated consultation.  This new information is
presented below. 

1997 ANALYSIS

The available data indicates that the incidental harvest fraction of
winter-run chinook was 0.54 for the 1992 brood year and 0.19 for the
1993 brood year.  The weighted two-year average is 0.40, if the ocean
tag recoveries and estimated spawning returns for the 1992 and 1993
hatchery-origin brood years are pooled.  Fishery impacts on the two
brood years occurred almost entirely during the 1994 and 1995 ocean
fisheries.  Ocean fisheries account for the total harvest impact on
winter-run chinook because in-river harvest was eliminated in 1990.

Based on the currently available escapement data for the 1989-1993
winter chinook brood years, the geometric mean adult replacement rate
for the winter-run chinook population is estimated to be 1.35.  This
rate is equivalent to a mean population growth rate of 35 percent per
generation since the species was listed in 1989 (See the January 1997
Addendum To The February 23, 1996, Biological Assessment for The
Fishery Management Plan for Commercial and Recreational Salmon
Fisheries off the Coasts of Washington, Oregon, and California as it
affects the Sacramento River Winter Chinook Salmon).  The 
1989-1993 base period was used in this analysis because it immediately
followed the period when actions were taken to improve the spawning,
rearing, and migration habitats of the population in the late 1980s. 

The specification of a required increase in the winter-run chinook
replacement rate was based on an estimation of the probabilities that
future 3-year replacement rates would be at least 1.0 (i.e. the
probability that the population will either remain stable or exhibit
positive growth) given varying increases in the observed 3-year
replacement rates for the 1989-1993 base period (see Table 5 in 1997
Addendum to the Biological Assessment).  Because of the two weaker
year classes in the population and the current low abundance of
winter-run chinook spawners relative to historical escapement levels,
NMFS has determined that the probability of achieving positive growth
must be at least 0.80.  Based on these probability estimates, there is
an 0.80 probability of achieving positive growth in the winter-run
chinook population if the adult replacement rate is increased by 31%
above the observed adult replacement rate for the 1989-1993 base
period.  A 31% increase in the base period adult replacement rate of
1.35 would increase the adult replacement rate to 1.77.  Any reduction
in the natural mortality rates associated with improvements to
spawning, rearing, and migration habitats occurring since 1995 would
increase the probability of achieving positive growth above 0.80.

NMFS acknowledges that the probability estimates of achieving positive
future growth rates are based on limited data and assumptions and that
the population may grow faster or slower depending on future in-river
and ocean survival conditions.  However, these estimates do provide a
means to evaluate the relative benefits to the population of
decreasing harvest impacts from current levels.  With respect to the
ocean fisheries, a complete closure of the chinook fisheries within
the geographic range of the winter-run chinook would be the strongest
possible measure that could be taken to increase escapement most
rapidly and to allow winter-run chinook the opportunity to recover to
healthy population levels.  However, NMFS has determined that it is
appropriate to use a probability of 0.80 for achieving positive growth
in the winter-run chinook population because this balances the need to
achieve immediate increases in the spawning escapement against the
economic impacts of further restricting or even closing the ocean
salmon fishery.  NMFS estimates that a 31% increase in adult
replacement rates will provide positive growth for the population in
approximately 8 out of 10 years.  The harvest reductions necessary to
achieve this increase are expected to reduce fishing in certain
components of the fishery, but NMFS has concluded this is still
consistent with the basic purposes of the Salmon FMP.  Harvest
reductions which do not achieve the 31% increase in adult replacement
rates will not provide adequate population growth, and, therefore, is
likely to  jeopardize the continued existence of winter-run chinook
salmon.
  
CONCLUSION

NMFS has concluded that a 31% increase in the adult replacement rate
above that observed for the 1989-1993 base period will reduce ocean
harvest impacts to a level that is not likely to jeopardize the
continued existence of winter-run chinook salmon, as well as, provide
for recovery of the species.  Therefore, the third component of the
Reasonable and Prudent Alternative contained in the March 8, 1996,
opinion has been updated to better reflect the new information and
additional analysis:

3. NMFS must reduce all ocean harvest related impacts to the winter-run 
chinook salmon population by a level that would achieve a 31%
increase in the adult 3-year replacement rate above the mean rate
observed for the 1989-1993 brood years.  

There is no new information to change the basis for the conclusions of
the 1996 opinion that ocean salmon fisheries managed under the
Council's Ocean Salmon FMP is likely to jeopardize the continued
existence of Sacramento River winter chinook.

In the absence of new and compelling information, the requirement for
a 31% increase in the adult replacement rate will remain in effect
through the 2001 salmon seasons.  NMFS will continue to monitor
incidental harvest impacts and escapement of winter-run chinook during
this period to better define the relationship between harvest impact
reduction and escapement.  At the end of this period, NMFS will review
the available information and reassess the need for restrictions on
ocean harvest.

REINITIATION OF CONSULTATION

Reinitiation of formal consultation is required if: (1) the amount or
extent of taking specified in the incidental take statement is
exceeded, (2) new information reveals effects of the action that may
affect listed species or critical habitat in a manner or to an extent
not previously considered, (3) the identified action is subsequently
modified in a manner that causes an effect to listed species or
critical habitat that was not considered in the Biological Opinion, or
(4) a new species is listed or critical habitat designated that may be
affected by the identified action.

Attachment