Marine Mammal Protection Act; Stock Assessment Report, 69136-69139 [E9-30900]

Agencies

• Fish and Wildlife Service
• DEPARTMENT OF THE INTERIOR

[Federal Register Volume 74, Number 249 (Wednesday, December 30, 2009)]
[Notices]
[Pages 69136-69139]
From the Federal Register Online via the Government Printing Office [www.gpo.gov]
[FR Doc No: E9-30900]


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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: https://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: https://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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