[Federal Register: December 30, 2009 (Volume 74, Number 249)]
[Notices]
[Page 69136-69139]
From the Federal Register Online via GPO Access [wais.access.gpo.gov]
[DOCID:fr30de09-106]
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DEPARTMENT OF THE INTERIOR
Fish and Wildlife Service
[FWS-R9-FHC-2009-N233; 40120-1113-4044-D2-FY10]
Marine Mammal Protection Act; Stock Assessment Report
AGENCY: Fish and Wildlife Service, Interior.
ACTION: Notice of availability of final 2009 revised marine mammal
stock assessment reports for two stocks of West Indian manatee;
response to comments.
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SUMMARY: In accordance with the Marine Mammal Protection Act of 1972,
as amended (MMPA), and its implementing regulations, we, the U.S. Fish
and Wildlife Service (Service), announce that we have revised our stock
assessment report (SAR) for each of the two West Indian manatee stocks
in the southeastern United States: The Florida manatee (Trichechus
manatus latirostris) stock and the Puerto Rico stock of Antillean
manatee (Trichechus manatus manatus), including incorporation of public
comments. We now make these two final 2009 revised SARs available to
the public.
ADDRESSES: To obtain the SARs for either or both of the West Indian
manatee subspecies, see Document Availability under SUPPLEMENTARY
INFORMATION.
FOR FURTHER INFORMATION CONTACT: West Indian Manatee in Florida: Jim
Valade, (904) 731-3116 (telephone) or Jim_Valade@fws.gov (e-mail).
West Indian Manatee in Puerto Rico: Marelisa Rivera, (787) 851-7297
(telephone) or Marelisa_Rivera@fws.gov (e-mail).
SUPPLEMENTARY INFORMATION:
Background
Under the MMPA (16 U.S.C. 1361 et seq.) and its implementing
regulations in the Code of Federal Regulations (CFR) at 50 CFR part 18,
we regulate the taking, transportation, purchasing, selling, offering
for sale, exporting, and importing of marine mammals. One of the MMPA's
goals is to ensure that stocks of marine mammals occurring in waters
under U.S. jurisdiction do not experience a level of human-caused
mortality and serious injury that is likely to cause the stock to be
reduced below its optimum sustainable population level (OSP). OSP is
defined as ``the number of animals which will result in the maximum
productivity of the population or the species, keeping in mind the
carrying capacity of the habitat and the health of the ecosystem of
which they form a constituent element.''
To help accomplish the goal of maintaining marine mammal stocks at
their OSPs, section 117 of the MMPA requires us and the National Marine
Fisheries Service (NMFS) to prepare a SAR for each marine mammal stock
that occurs in waters under U.S. jurisdiction. A SAR must be based on
the best scientific information available; therefore, we prepare it in
consultation with established regional scientific review groups. Each
SAR must include: (1) A description of the stock and its geographic
range; (2) a minimum population estimate, maximum net productivity
rate, and current population trend; (3) an estimate of human-caused
mortality and serious injury; (4) a description of commercial fishery
interactions; (5) a categorization of the status of the stock; and (6)
an estimate of the potential biological removal (PBR) level. The PBR is
defined as ``the maximum number of animals, not including natural
mortalities, that may be removed from a marine mammal stock while
allowing that stock to reach or maintain its OSP.'' The PBR is the
product of the minimum population estimate of the stock
(Nmin); one-half the maximum theoretical or estimated net
productivity rate of the stock at a small population size
(Rmax); and a recovery factor (Fr) of between 0.1
and 1.0, which is intended to compensate for uncertainty and unknown
estimation errors.
Section 117 of the MMPA also requires us and NMFS to review the
SARs (a) at least annually for stocks that are specified as strategic
stocks; (b) at least annually for stocks for which significant new
information is available; and (c) at least once every 3 years for all
other stocks.
A strategic stock is defined in the MMPA as a marine mammal stock
(a) for which the level of direct human-caused mortality exceeds the
PBR; (b) which, based on the best available scientific information, is
declining and is likely to be listed as a threatened species under the
Endangered Species Act of 1973, as amended (16 U.S.C. 1531 et seq.;
ESA), within the foreseeable future; or (c) which is listed as a
threatened or endangered species under
[[Page 69137]]
the ESA, or is designated as depleted under the MMPA.
Before releasing our draft SARs for public review and comment, we
reviewed the drafts with the Atlantic Regional Scientific Review Group,
which was established under the MMPA, and submitted them for an
internal technical review. In a June 12, 2009 (74 FR 28062), Federal
Register notice, we made available our draft SARs for the MMPA-required
90-day public review and comment period. Following the close of the
comment period, we revised the SARs based on public comments we
received (see below) and prepared the final 2009 revised SARs. Between
publication of the draft and final revised SARs, we have not revised
the status of either stock (i.e., strategic); however, we updated the
Nmin for the Florida manatee stock from 3,807 to 3,802,
based on a revised count provided by the Florida Fish and Wildlife
Conservation Commission. We addressed other concerns identified in the
public comments in the following section of this notice or by adding
text to the SARs for clarity.
The following table summarizes the final 2009 revised SARs for the
Florida and Puerto Rico stocks of the West Indian manatee, listing each
stock's Nmin, Rmax, Fr, PBR, annual
estimated human-caused mortality and serious injury, and status.
Table 1--Summary: Final Revised Stock Assessment Reports for the Florida and Puerto Rico Stocks of West Indian
Manatee
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Annual
estimated
average
West Indian manatee stocks Nmin Rmax Fr PBR human- Stock status
caused
mortality
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Florida........................... 3,802 0.06 0.1 12 87 Strategic.
Puerto Rico....................... 72 0.04 0.1 0 2 Strategic.
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Document Availability
Final Revised SAR for West Indian Manatee in Florida
You may obtain copies by any one of the following methods:
Internet: http://www.fws.gov/northflorida.
Write to or visit (during normal business hours) the Field
Supervisor, U.S. Fish and Wildlife Service, Jacksonville Field Office,
7915 Baymeadows Way, Suite 200, Jacksonville, FL 32256-7517; telephone
(904) 731-3336.
Final Revised SAR for West Indian Manatee in Puerto Rico
You may obtain copies by any one of the following methods:
Internet: http://www.fws.gov/caribbean/ES.
Write to or visit (during normal business hours) the Field
Supervisor, U.S. Fish and Wildlife Service, Caribbean Ecological
Services Office, P.O. Box 491, Boquer[oacute]n, PR 00667; telephone:
(787) 851-7297.
Responding to Public Comments
West Indian Manatee in Florida
We received comments on the draft SAR (74 FR 28062) from the
Atlantic Scientific Review Group, the Marine Mammal Commission, the
Center for Biological Diversity, The Humane Society of the United
States, the Save the Manatee Club, Defenders of Wildlife, and a private
citizen. We present issues raised in those comments, along with our
responses, below.
Comment 1: Commenters stated that the identification of four stocks
would facilitate management efforts, because SARs, developed for each
management unit, could more accurately identify unit-specific threats
and, therefore, better promote recovery within the management units.
Response: Current and previous Florida manatee management
activities have relied on the use of a state-of-the-art core biological
model (CBM) to assess manatee population status and threats to the
population as a whole and to assess status and threats in each of the
four management units. Service and State manatee management efforts
rely on the CBM for information on threats and consequently target
identified threat levels through management activities described in
respective recovery and management plans. For listed species, the
Service uses recovery plans to identify and address threats as
indicated by the ESA. Recovery Plans have been used effectively by the
Service and other resource agencies for over 30 years. Unit-specific
SARs for each of the four management units would be redundant and
provide no additional benefits to efforts to manage manatees within
these areas. As such, the Service will continue to assess and manage
threats to the population as a whole and within each of the four
management units. The SAR has been revised to more completely explain
this strategy.
Comment 2: Commenters took issue with the Service's conclusion that
total commercial fishery-related mortality and serious injury for the
Florida stock of manatees should be considered insignificant and
approaching a zero mortality and serious injury rate.
Response: For the period of record (2003-2007), manatee carcass
salvage and rescue programs recorded no commercial fishery-related
mortalities or any serious injuries related to commercial fisheries
activities. While the total number of manatee deaths attributed to
other anthropogenic sources exceeds the calculated PBR, the absence of
deaths and serious injuries specifically from commercial fishing
supports the Service's contention that commercial fisheries-related
takings, in and of themselves, should be considered insignificant and
approaching a zero mortality and serious injury rate.
Comment 3: Commenters stated that the Service's analysis of
seriously injured manatees was problematic.
Response: Absent a Service definition of ``serious injury,'' an
agency interpretation and analysis of manatee injury records is
difficult at best and a thorough, meaningful analysis cannot be
concluded at this time. The SAR has been revised to reflect this
concern.
Comment 4: A commenter recommended that the Service include a table
showing the results of abundance surveys over time.
Response: The Service elected not to include such a table because
many readers may misinterpret differences in counts as indicative of
changing population trends. The most recent minimum population estimate
is the most significant, relevant data point and is included in the
final SAR for the Florida manatee.
[[Page 69138]]
Comment 5: A commenter questioned the Service's determination that
six cited fishing line and associated gear-related deaths did not
involve actively fishing commercial fisheries-related gear.
Response: Each of the cited deaths involved the ingestion of
lengths of monofilament line accompanied by a single hook, a lure, and/
or a fishing weight. Given the manatees' herbivorous nature, it is
unlikely that a manatee would be attracted to actively fished gear of
this nature. Furthermore, nearshore, commercial fisheries that rely on
gear of this nature are virtually unknown (commercial trotline fishers
do fish in these waters; however, their gear typically includes lengths
of monofilament line or other line types containing multiple hooks).
Given the absence of inshore commercial line fisheries that utilize the
gear found in these animals, these deaths should not be correlated with
commercial fishing activities.
Comment 6: Two commenters questioned the use of an Rmax
based on the maximum net productivity rate calculated for the Upper St.
Johns River management unit.
Response: Guidance for developing SARs supports using measured
growth rates greater than recommended default values, especially when
using data that includes the entirety of a closed population to
minimize unknown biases. Growth rates for the manatees in the Upper St.
Johns River management unit have been accurately assessed and the
population in this unit most closely approximates a closed population.
As such, the Service believes that it has identified a proper
Rmax.
Comment 7: Commenters questioned using serious injury and mortality
data from the 2003 through 2007 period when more recent data are
apparently available.
Response: Pertinent datasets used to prepare the SAR included data
from the Florida Manatee Rescue, Rehabilitation, and Release Database
and the Florida Manatee Mortality Database. At the time of writing,
data from the manatee rescue program database were complete through
December 31, 2007 and data for calendar year 2008 were not then
available. Preliminary mortality database information was available
through December 31, 2008, although data for calendar year 2008 had not
been verified for accuracy at the time of writing. Consistent with
mandates to use the best available information, the Service elected to
use data from the 2003 through 2007 period inasmuch as data from this
period had been thoroughly reviewed for completeness and accuracy at
the time of writing.
Comment 8: Commenters recommended that the Service continue to take
the steps needed to better define OSP and to gather more information on
manatees in the Southwest management unit.
Response: The Service is supporting research activities that will
provide greater insights into OSP for the Florida manatee and provide
more current assessments of population trends and threat levels in both
the stock and management unit populations.
West Indian Manatee in Puerto Rico
We received comments on the draft SARs (74 FR 28062) from the
Atlantic Scientific Review Group, the Marine Mammal Commission, the
Center for Biological Diversity, and The Humane Society. We present
issues raised in those comments, along with our responses, below.
Comment 1: The Service should provide a better explanation for
recognizing the Puerto Rico manatee as a single stock instead of
recognizing the Puerto Rico manatee as consisting of different stocks
based on the geographical distribution of haplotypes in Puerto Rico.
Response: We have revised the SAR to discuss recent research
regarding the geographic distribution of haplotypes in Puerto Rico.
Slone et al. 2006 indicates that haplotype (mitochondrial DNA)
distribution is further geographically divided in Puerto Rico. For
example, only the A haplotype (a haplotype also unique to Florida) was
found on the north side of the island and only the B haplotype was
observed in the south. A mixture of A and B haplotypes was observed on
both the east and west coasts of the island, suggesting that mixing
occurs between the northern and southern groups. However, the
mitochondrial DNA is maternally inherited and is not reflective of gene
flow from the more adventurous males. Radio-tagging techniques in
Puerto Rico have documented general behavior of manatee populations, in
which males seem to move more extensively than females (Slone et al.
2006). Males may travel hundreds of kilometers while mother/calf
distribution patterns could be more restricted. The authors state that
if male movements are made during the breeding season, then relatively
healthy mixing between geographical areas established by females might
be expected. Further research by Kellogg (2008) indicates that nuclear
DNA subpopulation separation was not as severe, suggesting that the
manatees in Puerto Rico do travel and breed throughout the population
to some degree. Based on the above information, we believe that the
Puerto Rico manatee stock should not be divided into two separate
stocks.
Comment 2: The commenter suggested that the current population
trend of the Puerto Rico manatee appears to be relatively stable rather
than increasing.
Response: The Service agrees with the comment and has revised the
SAR accordingly.
Comment 3: The commenter recommended that the statement ``the
number of strandings currently reported to DNER may represent a true
value of mortality'' should be considered as a hypothesis rather than a
conclusion.
Response: The Service agrees and has revised the SAR accordingly.
Comment 4: The commenter recommended that the Service obtain
information necessary to determine the optimum sustainable population
(OSP).
Response: OSP has not been determined for any population stock of
West Indian manatee; however, both the Florida and Puerto Rico stocks
are considered strategic based on their listing under the ESA. From
1992-2002 and 2009, Service synoptic aerial surveys have consistently
counted calves and the entire population is considered stable. We are
evaluating aerial census methodology with the goal of establishing more
reliable population estimates.
Comment 5: The commenter recommended the Service fill in data gaps
by gathering more information on entanglements, collisions, and
bycatch.
Response: As stated in the SAR, manatee deaths in Puerto Rico have
been reported for decades. Since 1990, the documentation of manatee
mortalities in Puerto Rico has been conducted by the Caribbean
Stranding Network (CSN). In 2006, the Department of Natural and
Environmental Resources (DNER) Marine Mammal Stranding Program (MMSP)
took over these duties. This program is implemented with the assistance
from the CSN, the Puerto Rico Zoo, and commonwealth law enforcement
officials. We believe that the manatee death reports provided by the
DNER MMSP, with all the help mentioned above, are a consistent and
reliable manner to gather data on entanglements, collisions, and
bycatch.
Comment 6: Commenters disagree with the Service's conclusion that
commercial fisheries-related incidental mortality and serious injury of
manatees in Puerto Rico and the U.S. Virgin Islands should be
considered minimal or approaching zero.
[[Page 69139]]
Response: The Service acknowledges that there may be limitations on
the available fisheries data because some takings could occur and may
not be observed or reported. However, protocols for necropsies and
assigning probable cause of death categories are reviewed thoroughly.
Table 1 of this SAR shows watercraft as the only human related deaths.
The only possible evidence for commercial fisheries interaction would
be within the 34 percent undetermined cause of death (COD) category.
Undetermined COD means that assessment of a natural or human related
cause was negative (no evidence that COD can be assigned to any of the
available categories, either natural or human related). In addition, we
believe that manatees injured by commercial fisheries interactions
would most likely present signs of the activity and every necropsy
includes a specific evaluation of human interactions. From 1990-2008,
only one manatee had COD related to commercial fisheries interaction.
In 2006, one freshly dead manatee was found with its right flipper
entangled in monofilament and still this COD was deemed undetermined.
In accordance with the previous statements and the presence of current
bans and restrictions prohibiting the use of nets in coastal Puerto
Rican waters, the Service believes that incidental mortality and
serious injury related to commercial fisheries in Puerto Rico and the
U.S. Virgin Islands should be considered minimal or approaching zero.
Comment 7: The SAR should provide at least some summary information
to indicate the type(s) of habitat degradation adversely affecting
manatees.
Response: We have revised the SAR to include examples of habitat
degradation.
Comment 8: The commenter recommended that the Puerto Rico manatee
stock be considered separately from the Florida manatees in terms of
recommendation for down-listing.
Response: The Service acknowledges the comment made; however, the
SAR is conducted according to the MMPA and does not address issues
under Section 4 of the ESA.
Comment 9: The commenter opposed any efforts to down-list the
status of manatees from endangered to threatened.
Response: The Service acknowledges the comment made; however, the
SAR is conducted according to the MMPA and does not address issues
under Section 4 of the ESA.
Comment 10: The commenter is concerned about the lack of reliable
data on abundance and mortality.
Response: The Service acknowledges the commenter's concern and is
currently evaluating aerial census methods to establish more reliable
population estimates. We do not believe that mortality records lack
reliability. As provided in our response to Comment 5 above, CSN had
been documenting manatee mortalities in Puerto Rico since 1990.
Although the DNER MMSP took over these duties in 2006, the program is
implemented with assistance from the CSN, the Puerto Rico Zoo, and
commonwealth law enforcement officials. We believe that the manatee
death reports provided by the DNER MMSP, with all assistance of these
partners, are a consistent and reliable manner to gather mortality
data.
Comment 11: The commenter asked why so many released manatees have
died in Puerto Rico.
Response: After reviewing the data received by the CSN, we
recognized there was an error and have revised the SAR accordingly.
From 1990 to 2005, a total of 23 manatees were rescued by the CSN. Of
these, two were rehabilitated and released, two were released
immediately after rescue, 17 died in rehabilitation, one died in
transport, and one is currently in rehabilitation. Of the four manatees
that were released, one died one year after its release.
Additional References Cited
West Indian Manatee in Puerto Rico
Kellogg, M.E. 2008. Sirenian Conservation Genetics and Florida Manatee
(Trichechus manatus latirostris) cytogenetics. Doctoral dissertation,
University of Florida, Gainesville, FL. 159 pp.
Sloan, D.H., J.P. Reid, R.K. Bonde, S.M. Butler, and B.M. Stith. 2006.
Summary of the West Indian manatee (Trichechus manatus) tracking by
USGS-FISC Sirenia Project in Puerto Rico. Report Prepared for the U.S.
Fish and Wildlife Service. 9 pp.
Authority: The authority for this action is the Marine Mammal
Protection Act of 1972, as amended (16 U.S.C. 1361 et al.).
Dated: December 14, 2009.
Sam Hamilton,
Director, Fish and Wildlife Service.
[FR Doc. E9-30900 Filed 12-29-09; 8:45 am]
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