Comments from PIFSC on the Atlantic HMS FMP Sections 3.8.2 through 3.8.5
(the standardized bycatch reporting methodology), section 4.1.2
(Time/Area Closures), Chapter 10 (EFH), Appendix A (Time/Area Closures)
and Appendix B (EFH).

January 9, 2006

Prepared by Chris Boggs and Keith Bigelow

**GENERAL COMMENTS:**

This consolidated FMP is a mammoth undertaking. The breadth and detail
of the information that has been reviewed, considered and presented is
staggering. The quality of the data information is highly variable and
the document does a good job of indicating problems and issues with data
sources, and with the appropriateness of their application to management
measures. And the document identifies the many areas that require
improvement in information and management alternatives based on future
study and deliberation. The greatest limitations to the overall products
reviewed by PIFSC seems to be in the closed area alternatives, but this
is to be expected. The other sections reviewed by PIFSC do not lead
directly to management decisions that immediately affect fishery
operations.

The section on bycatch could be improved by some clarification of
terminology (as indicated in the specific comments). A few areas of
information regarding bycatch mortality appear to have been missed, but
the document is a comprehensive and thorough compendium of our current
position in terms of knowledge and application to management issues as
well as the needed direction for improvement. The theory behind
establishing a standardized methodology for precision and accuracy in
bycatch estimation exceeds the practice, which has been slow to develop
and thus is not extensively covered. However the agency is hamstrung by
lack of resources even to conduct analyses of cost/improvement ratios in
any but a few fisheries, let alone to increase the myriad of observer
and other monitoring programs that would be required for all fisheries.
Documenting the present status of this effort is the appropriate first
step for the FMP, which can present no more than what is the best
available information.

The section on area closures presented the most difficulty and the
specific comments may prompt clarification of the presentation. The
rationale for the preferred alternatives could use strengthening where
indicated. It is clear that a very large amount of information and
comment was considered and a host of differing objectives had to be
balanced. This will always produce choices which reflect compromise. The
rationale for some of these choices appears to need some bolstering,
especially as they face challenge from specific interest groups.

The section on EFH benefits from a greater wealth of published
scientific information than the other sections, and results in no
specific management alternatives to be considered at this time. The one
identified area for future consideration appropriately awaits further
data collection (bottom longline impacts on reef habitat). The rationale
for expecting little impact of the fisheries on EFH at present is
convincing. The issues for this section revolve around the practice of
EFH designation, and these issues are well described and critiques from
previous reviews made available. To be more thorough on scientific
content this section would have to become encyclopedic, which would not
be appropriate to its purpose. Possible errors for one species (specific
comment) stood out only because of the focus by the PIFSC on the habitat
of this species. The coverage of coastal anthropogenic effects on the
HMS EFH is much more thorough than in our FMP for the central and
western Pacific...but that seems appropriate given the greater ratio of
coasts to ocean.

**SPECIFIC COMMENTS:**

**Bycatch**

**3.8**

Regarding the 2^nd^ par:

"The national goal of the Agency's bycatch plan activities is to
implement conservation and management measures for living marine
resources that will minimize, to the extent practicable, bycatch and the
mortality of bycatch that cannot be avoided. Inherent in this

goal is the need to avoid bycatch, rather than create new ways to
utilize bycatch. The plan also established a definition of bycatch as
fishery discards, retained incidental catch, and unobserved mortalities
resulting from a direct encounter with fishing gear."

Fishery Councils may disagree that utilization (and thus reduction) of
bycatch is not a valid goal under Magnusson. Can the statement to the
contrary be supported more thoroughly?

And in the next section

**3.8.1 Bycatch Reduction and the Magnuson-Stevens Act**

"The Magnuson-Stevens Act defines bycatch as fish which are harvested in
a fishery, but

which are not sold or kept for personal use, and includes economic and
regulatory discards. Fish is defined as finfish, mollusks, crustaceans,
and all other forms of marine animal and plant life other than marine
mammals and birds. Seabirds and marine mammals are therefore considered
'incidental catch.'"

Rather than re-visit here all the discussion about the National Plan's
different (from Magnuson) definition of bycatch, it is suggested that
the text avoid using incidental catch in two contradictory ways in two
succeeding paragraphs. There are clearer and widely-used terms for catch
of seabirds and marine mammals, such as "takes of protected species" or
"protected species interactions". NOAA Fisheries claims important
successes in reducing bycatch" when referring to reductions in seabird
and mammal takes, and can continue to do so in a broadly understood use
the term "bycatch". But it isn't a broadly understood that "incidental
catch" to refer to protected species. "Incidental take" might be better
understood.

Next par

"National Standard 9 of the Magnuson-Stevens Act requires that fishery
conservation and

management measures shall, to the extent practicable, minimize bycatch
and minimize the mortality of bycatch that cannot be avoided. In many
fisheries, it is not practicable to eliminate all bycatch and bycatch
mortality. Some relevant examples of fish caught in Atlantic HMS
fisheries that are included as bycatch or incidental catch..."

Should turtles also be listed as examples? They were includsed as fish
bycatch under Magnuson-Stevens (was this changed recently?) and some of
the subsequently listed options for bycatch reduction in this section
are specific to turtles and have no documented utility for reducing any
other bycatch (e.g. large circle hooks reduce turtle bycatch, but
otherwise reduce mostly injury or mortality of other bycatch).

Then in a following par

"Therefore, to totally eliminate bycatch of all non-target species in
Atlantic HMS fisheries would be impractical. The goal then is to
minimize the amount of bycatch to the extent practicable and minimize
the mortality of species caught as bycatch."

This statement is laudably practical, and such a statement was requested
in the council/public reviews. However, the statement and the preceding
discussion leave moot the issue of whether incidental takes of protected
species (or just "fish" including \[?\] turtles) are addressed by the
statement. The latter (just fish bycatch) is implied by the heading
"Magnuson-Stevens" but the preceding section mentioned broader issues,
and the mention of incidental takes in this section implicates protected
species due to the use of incidental takes to refer to them in the
previous section.

**3.8.2 Standardized Reporting of Bycatch**

"The National Bycatch Report (NMFS, 2004a) contains an indepth

examination of the issues of precision and accuracy in estimating
bycatch. Precision of an

estimate refers to its variability, or how repeatable the estimate is.
The more precise an estimate is, the less variable it is. Precision of
estimates is usually expressed in terms of a statistical value, the
coefficient of variation (CV) of the estimate (NMFS, 2004a), which is
the ratio of the square root of the estimate (also known as the standard
error) to the estimate itself."

Both yellow highlighted words should be "variance". I'm not sure the
blue highlighted captures the proper meaning. Marti McCracken (PIFSC
mathematical statistician) provided the following, more rigorous
explanation which might avoid some criticisms regarding your use of
"variability"(for your consideration).

"The National Bycatch Report( NMFS, 2004a) contains an in depth
examination of the issues of precision and accuracy in estimating
bycatch. Accuracy refers to the closeness between the estimated value
and the (unknown) true value that the statistic was intended to measure.
Precision refers to how closely multiple measurements of the same
statistic cluster to one another when obtained under the same protocol.
The more precise an estimate is the tighter the cluster. The precision
of an estimate is often expressed in terms of the coefficient of
variation (CV) defined as the standard error of the estimator divided by
the estimate. A precise estimate is not necessarily an accurate
estimate."

One might add that "A more precise estimate is more easily distinguished
from a second estimate (different time, place, treatment, etc)
especially when they are close in value. Testing hypotheses about
changes or differences from reference values or limits is the motivation
for our interest in the precision and accuracy of bycatch estimates. We
frequently need to evaluate whether or not bycatch is altered by events
or actions.

Three pars down the document states:

"The CV of an estimate can also be reduced and the precision increased
by increasing

sample size.

Delete the highlighted "also" which is confusing because no other means
of improving CV has yet been mentioned. The prior paragraph listing of
randomization, stratification, sampling allocation, and testing for bias
pertain to "while striving to achieve accuracy" not to precision.
Balancing "precision goals and the least amount of observation effort"
is basically the issue of what sample size (= precision) one can afford.

In the following paragraph:

"While the relationship between precision and sample size is relatively
well known

(NMFS, 2004), the relationship between sample size and accuracy is not
so easily determined."

It might be better to say "is not reliable" or "can often be complex" to
better anticipate the following paragraph. More samples can mean more or
less accuracy. For example, when observer coverage is increased late in
a season to catch up to a target level of coverage, the increased sample
size may reduce accuracy if not properly stratified and weighted.

**3.8.2.3 *Shark Bottom Longline Fishery***

The par starting with "Effective August 1, 2001 ..." is u necessarily
reproduced in full in the following Section 3.8.2.4.

**3.8.4 Evaluation and Monitoring of Bycatch**

3^rd^ par. Fix "estimated...estimates". It seems overly cautious to
apologize for a lack of bycatch estimates in harpoon fisheries. How does
one harpoon an unwanted catch? A proper approach is used under mortality
in the next section and should be used here as well.

**3.8.5 Bycatch Mortality**

***3.8.5.2 Mortality by Fishery***

*Pelagic longline* Last sentence says to see section 3.4.1 for more
information, inferring more information will be found there on "hook
location, trailing gear and injury status of protected species
interactions". I couldn't find that information in section 3.4.1 (did I
miss it somewhere?). There is a literature on estimating turtle longline
mortality, including US policies for estimating turtle mortality from
hook location and trailing gear, and extensive tagging studies of
post-release mortality, that could be cited and discussed. This lack is
particularly at odds with the detailed discussion given on tagging study
of released fish mortality below in the recreational handgear section.
Nor is the turtle bycatch condition (alive/dead) or estimated
post-release mortality covered in the ESA section which follows...where
some information on marine mammal and seabird mortality is provided.
Turtles seem to be given comparatively short shrift. The longline turtle
bycatch mortality estimation also relies on gear configuration (i.e.
shallow and deep setting). And the illustration of longine gear
configuration in Section 3.4.1 taken from the Honolulu Advertiser
(p.3-89) may be misleading in several ways. For one, this illustration
has a strong vertical exaggeration/horizontal compression that gives a
"wall of death" impression of the gear configuration. There are better
technical illustrations of longline gear configuration in the
literature. Second, none of the 5 types of US longline fishing described
underneath the figure is close to the illustrated "tuna set"
configuration. The latter best describes certain Asian and European
fleets in the Atlantic, but not the US. This should be made clear. In a
world context, all of the U.S. fisheries (except maybe the Carribean
fishery?) are relatively shallow compared with Asian tuna longline
fishing.

*Purse Seine Fishery*

This section is hard to believe. There are huge finfish bycatch
mortality issues in Pacific tuna purse seines. The fish can not be
easily released alive. Small fish are gillnetted by the mesh and larger
ones smothered in the brail. There is an active research program in
Europe looking for grids or gratings that can release purse seine
bycatch that could be referenced. Pacific purse seine fisheries bycatch
of small bigeye and yellowfin tunas is a major cause of overfishing, and
there are also huge discarded (dead) bycatches of mahimahi, sharks, and
other finfishes documented in IATTC reports. Why assume that discards
are small and can easily be released in the U.S. Atlantic purse seine
fishery for bluefin? Is it a very different operation? Explain.

*Bottom Longline Fishery*

*Shark Gillnet Fishery* Again both of these sections refer the reader to
section 3.4.?.? for more information but there is no information on
mortality in the cited sections.

**4.1.2 Time/Area Closures**

Alternative B1 is to maintain the existing time/area closures; no new
time/area closures (No Action). There are no tables which present the
results from Alternative B1. Isn't this necessary as some of the
closures were not in effect (e.g. Mid-Atlantic Closure (effective Jan.
1, 2005, Northeast Distant Restricted (effective June, 30, 2004)) for
the entire 2001−2003 period? Maybe these closures are for non-Pelagic
fishing. Additionally, on p. 4-21 it says "To determine the
effectiveness of the current closures, NMFS compared data prior to
implementation of the closed areas (1997−1999) with effort and catch
rates from 2001−2003 for various species". I couldn't locate this
comparison or a reference. As such this would be a different comparison
then Alternatives B2−B7 which compare catch and effort from 2001 to
2003.

Statistical validity − under-reporting in logbooks, assumptions on the
redistribution of fishing effort and CPUE. Perhaps the following is
addressed in additional documentation, but these are concerns regarding
the presented statistics and associated assumptions for the catch and
effort analyses. While I realize that the time-frame of a final FMP is
rapidly approaching, perhaps the statistical validity of some of these
concerns can be better documented or referenced.

Two data sources are used -- the Pelagic Observer Program (POP) data and
Pelagic Longline Logbook (PPL) data. There is no doubt that various
species will either be non-reported or under-reported in logbook data.
Figures 4.1 through 4.8 clearly illustrate difference in interaction
rates between PPL and POP sets. A comparison of Table 4.5 and 4.6 (A.7)
indicates that the percent reduction for most species is greater with
the Pelagic Longline Logbook data than Observer data which may have led
to the statement for Alernative B2(a) that "the percent reductions in
most bycatch were similar for the observed and reported data, and for
the year-round versus May through November closures (4−26)". This is
counter-intuitive given the comparison of Figures 4.1−4.8, but may
relate to spatio-temporal effects. Is there any analysis or reference by
NMFS which compares observer and logbook data for observed longline
sets? The absolute numbers and percent reductions for bycatch species
using logsheet data would correspond to a minimum value given
difficulties associated with under-reporting. In contrast, the percent
reductions/increases for target species are probably more realistic as
they are more accurately reported in logbooks.

The assumptions on redistribution of effort and application of
corresponding CPUE values are problematic. The current model assumes
that effort will be uniformly distributed into all remaining ocean
areas. Is a uniform distribution a valid assumption, or could other more
plausible assumptions be considered? Specifically, if a portion of the
Gulf of Mexico (GOF) is closed, is it reasonable to redistribute effort
within open areas of the GOF as well as the Atlantic? While I'm not
familiar with longline fleet movements under this FMP, do the fleets
routinely move between the GOF and Atlantic and vice-versa? As noted
periodically throughout the document, there are interactions that
increase due to closed areas because interaction rates are higher in the
open areas (e.g. loggerhead turtles). While the uniform distribution is
easy to comprehend, could another redistribution scenarios be considered
to redistribute effort in the same ocean basin?

The CPUE values are estimated as the number of animals per 1,000 hooks.
I could not locate any reference as to how CPUE indices were constructed
given a prevalence of zero observations. Given that some animal
interactions (e.g. bluefin tuna, sea turtles) represent rare events it
would be better to represent the redistribution of effort and
corresponding CPUE by a statistical sub-sampling technique rather than a
mean CPUE. This would also provide corresponding confidence intervals
for bycatch reduction, albeit it is still based on the aforementioned
logbook data with potential under-reporting.

I couldn't locate any objectives or decision matrix in deciding on the
preferred HMS alternatives. Most of the decisions seem to correspond to
a percentage of reduction/increases for target species/bycatch and
associated economics. Perhaps consider a re-evaluation of those
alternatives that represent a moderate closed area, such as B2(a) and
B2(f) which provide substantial bycatch reduction of white and blue
marlin, sailfish and sea turtles. With the redistribution of effort,
these areas could have resulted in negative ecological impacts with
increased discards of swordfish, bluefin and bigeye tuna. Do the
negative impacts result from a redistribution to the Atlantic and
associated higher catch rates?

The rational for preferred alternative B4 and benefit to HMS species
appears extremely vague. Alternative B4 implements complementary HMS
management measures in Madison-Swanson and Steamboat Lumps Marine
Reserves. There is no indication as to the spatial size of such reserves
(it's not illustrated on any of the maps) and curiously there is the
statement that "any positive ecological impacts on HMS are expected to
be minimal (4-34)". Again, I'm not familiar with Gulf issues, but if
this is a gag grouper issue why can't the Gulf Council enact appropriate
regulations as the gag grouper problems and pelagic fishing exploitation
appear mutually exclusive?

Preferred alternative B5 appears straightforward, but I'm not certain
that it adds much more to the status quo. Doesn't the current FMP have
criteria for regulatory framework adjustments for closures, given the
fact that closures currently exist?

**Appendix A** was a very necessary appendix for following the
discussion in section 4.1.2.

**Chapter 10 --** see general comments

**Appendix B --** see general comments

***B.1.1.2 Atlantic Bigeye Tuna (Thunnus obesus)***

Regarding "Although its distribution with depth in the water column
varies, it is regularly found in deeper waters than are other tuna - to
a depth of 250 m." As a Pacific expert this seems surprising to me,
since archival tag data show routine behavior to 400 m and deeper, and
much older studies also indicate these depths as part of the habitat in
the Pacific.

**Habitat associations** see the IATTC proceedings on the World Bigeye
Tuna workshops. There is an extensive literature on dissolved oxygen and
temperature as the limiting factor on bigye tuna depth distribution.
Since it is a world meting with a review for each ocean it may cover
differences between oceans that could satisfactorily explain this
discrepancy.