Taking of Threatened or Endangered Marine Mammals Incidental to Commercial Fishing Operations; Issuance of Permit

Summary:

NMFS hereby issues a permit for a period of 3 years, to authorize the incidental, but not intentional, taking of four stocks of threatened or endangered marine mammals by the California/Oregon (CA/OR) drift gillnet fishery. The four stocks are: fin whale, California/Oregon/Washington stock; humpback whale, California/Oregon/Washington-Mexico stock; Steller sea lion, eastern stock; and sperm whale, California/Oregon/Washington stock. This authorization is based on a determination that this incidental take will have a negligible impact on the affected marine mammal stocks.

Table of Contents

Dates:

This permit is was issued on October 24, 2000, and is effective through October 24, 2003.

Addresses:

Copies of the reference materials and Environmental Assessment (EA) may be obtained from Protected Resources Division, National Marine Fisheries Service, Southwest Region, 501 West Ocean Blvd., Suite 4200, Long Beach, CA 90802-4213. Attention: Tim Price.

For further information contact:

Tim Price, NMFS, Southwest Region, Protected Resources Division, (562) 980-4029.

Supplementary information:

Section 101(a)(5)(E) of the Marine Mammal Protection Act (MMPA) (16 U.S.C. 1371(a)(5)(E)) requires the authorization of the incidental taking of individuals from marine mammal stocks listed as threatened or endangered under the Endangered Species Act (ESA) in the course of commercial fishing operations if NMFS determines that (1) the incidental mortality and serious injury will have a negligible impact on the affected species or stock; (2) a recovery plan has been developed or is being developed for such species or stock under the ESA; and (3) where required under section 118 of the MMPA, a monitoring program has been established, vessels engaged in such fisheries are registered in accordance with section 118 of the MMPA, and a take reduction plan has been developed or is being developed for such species or stock.

On June 6, 2000 (65 FR 35904), NMFS proposed the issuance of a permit, for a period of 3 years, to authorize the incidental, but not intentional, taking of four stocks of threatened or endangered marine mammals by the CA/OR drift gillnet fishery under section 101(a)(5)(E) of the MMPA.

Four letters of comment were received concerning the proposal for issuance of a permit. All of these letters were in opposition to the issuance of a permit.

Comment 1: Two commenters requested that the comment period be extended to provide additional time to prepare a detailed response.

Response: NMFS believes that a 45-day comment period was sufficient time for public comment and is consistent with the process established at 50 CFR 229.20 for issuance of a permit to authorize the incidental take of threatened or endangered marine mammals species under section 101(a)(5)(E) of the MMPA.

Comment 2: One commenter felt that a permit should not be issued if the permit would allow the incidental taking of threatened or endangered species under the ESA.

Response: Under section 101(a)(5)(E) of the MMPA, the Secretary of Commerce (Secretary) must allow the incidental, but not intentional, taking of marine mammals from a species or stock designated as depleted because of its listing as an endangered or threatened species under the ESA if the Secretary determines that the incidental mortality and serious injury from commercial fisheries will have a negligible impact on such species or stock, that a recovery plan has been developed or is being developed, and that the provisions of section 118 are being met. The Secretary cannot refuse to issue a permit under section 101(a)(5)(E) if the conditions set forth in the MMPA have been met.

Comment 3: One commenter stated that NMFS should not issue a 101(a)(5)(E) permit to the CA/OR drift gillnet fishery because there is incidental take of sperm whales, marlin, skipjack tuna, and blue sharks.

Response: The potential biological removal (PBR) level for the California/Oregon/Washington sperm whale stock is 2.0 whales per year. The CA/OR drift gillnet fishery is the only fishery likely to incidentally take a sperm whale from this stock. Using a 3-year average (1997-1999), the mean annual mortality and serious injury rate from the CA/OR drift gillnet fishery is estimated to be 1.7 sperm whales. In 1998, one sperm whale was observed killed in a net that was not in compliance with the Pacific Offshore Cetacean Take Reduction Plan (Plan) developed for the CA/OR drift gillnet fishery. The Pacific Offshore Cetacean Take Reduction Team (Team) recommended no further strategies to reduce sperm whale entanglements be implemented until the effectiveness of pingers is better understood. The estimated annual mortality using a 3-year average is less than PBR and would cause no more than a 10-percent increase in the time needed to achieve recovery. NMFS has determined that an activity that slows the rate of recovery of depleted marine mammals to pre-exploitation levels by no more than 10-percent delay is considered a “negligible impact” for purposes of issuing a permit under section 101(a)(5)(E) of the MMPA. The incidental taking of marlin, skipjack tunas, and blue shark is not relevant to the determination about issuing a permit under section 101(a)(5)(E) of theMMPA, which addresses only marine mammals listed under the ESA.

Comment 4: One commenter indicated that NMFS is abandoning its current formula for determining the “negligible impact” threshold in favor of a calculation that substantially decreases protection and increases risks for listed species.

Response: The new approach for determining negligible impact is consistent with the guidelines prepared by the Marine Mammal Commission (Commission), and submitted to NMFS in 1990 to be used in its development of a regime to govern the mortality and serious injury of marine mammals incidental to commercial fishing operations. In the guidelines, the Commission stated that a negligible impact would cause no more than a 10-percent delay in a severely depleted stock’s recovery. This commenter correctly notes that the criterion the determination used as an initial estimate of the negligible impact threshold is different than that used in 1995 when permits under MMPA section 101(a)(5)(E) were issued for the first time. While this new approach may be slightly less conservative than the approach used in 1995, the approach does not significantly affect the recovery rate of the stock.

Comment 5: By allowing fisheries related mortality up to 100 percent of the PBR level, the proposal essentially renders the margin of safety created by the recovery factor meaningless and, thereby, reduces protection for listed species.

Response: The approach used in this negligible impact determination could authorize the mortality and serious injury to equal the PBR level of some stocks of marine mammals (i.e., those stocks with a recovery factor of 0.1 in the PBR equation) and does reduce protection as compared to the extremely conservative approach previously used. The protection, although reduced from the former approach (10 percent of PBR), is appropriate for the stocks involved and is consistent with the Commission's recommendation to NMFS for a quantitative estimate for negligible impact. The legislative proposal that NMFS submitted to Congress in 1992 adopted the Commission's recommendation of 10 percent delay in recovery in a statement that 90 percent of an endangered marine mammal stock's annual production should be reserved for recovery and that only 10 percent should be authorized for removal incidental to human activity. Intensive simulation modeling of marine mammal populations showed no more than a 10-percent delay in recovery would result when human-caused mortality was below a threshold defined by one-tenth of the product of the stock's minimum population estimate (Nmin) and one-half of its maximum net productivity rate (1/2 Rmax) (i.e., 0.1 * Nmin * 1/2 Rmax). Such a threshold is the equivalent of a stock's PBR when calculated with a recovery factor of 0.1. When applying the former criterion (10 percent of PBR) to a stock with a recovery factor of 0.1 in the PBR equation, the result could be an order of magnitude more restrictive than is necessary to achieve the stated goal of negligible impact. As in the determinations for the 1995 permit, NMFS uses this threshold as a starting point in the determination, rather than a mechanical application of a general formula, to ensure that the incidental mortality and serious injury would cause no more than a negligible impact.

Comment 6: One commenter suggested that it was inappropriate and scientifically unsound to issue permits for increased takings of federally listed marine mammal species based on such a small sample size and limited amount of monitoring data (low observer coverage) obtained since implementation of the Plan.

Response: NMFS disagrees. The issuance of a permit to allow for the taking of marine mammal species listed under the ESA does not authorize an increase in taking. The issuance of a permit authorizes the fishery to lawfully take species listed under the ESA provided the incidental taking is negligible. Observer coverage for 1997 (the effective date of the Plan was October 30, 1997), 1998, and 1999, has averaged 20 percent. Twenty-percent observer coverage is considered adequate for estimating protected species interactions in the CA/OR drift gillnet fishery. During this time, there was only one sperm whale observed taken, and this take was in a net that was not equipped with “pingers” (acoustic deterrent devices) and thus was not deployed in compliance with the Plan. More importantly, overall cetacean mortality has decreased for sets in which pingers are used.

Comment 7: One commenter indicated that a permit should not be issued because the sperm whale takes from the Mexican drift gillnet fishery were not considered.

Response: NMFS disagrees. The CA/OR drift gillnet fishery takes sperm whales from the California/Oregon/Washington stock. For management purposes, this stock does not include animals of the Mexican sperm whale population. Although large populations of sperm whales exist in waters south of the California/Oregon/Washington region, there is no evidence of sperm whale movements into this region. Moreover, NMFS understands that Mexican fishermen have converted their drift gillnet fleet along Baja California to longline vessels.

Comment 8: One commenter noted that the 1999 Stock Assessment Report (SAR) for sperm whales calculated an incidental mortality by the fishery of 4.6 animals per year, using a 5-year average, and the draft 2000 SAR calculated a mean annual take of 2.5 whales, using 1997 and 1998 data, which is greater than the calculated PBR level. The commenter also stated that the use of only 2 years of data is problematic, given the small sample size and the low level of observer coverage.

Response: NMFS disagrees. To more accurately reflect entanglement rates after the implementation of the Plan (minimum 6-fathom extenders, skipper education workshops, and the use of pingers), the Scientific Review Group (SRG), which consists of independent (non-Federal) individuals with expertise in population dynamics and modeling, recommended that mortality averaging should use data from 1997 (the year the Plan was implemented) and beyond (up to 5 years). The data presented in the 1999 SARs were collected before the Plan was implemented. Therefore, for all marine mammal species incidentally taken in the fishery, mean annual mortality estimates in the SARs will use data collected since the implementation of the Plan. At the time that the draft 2000 SARs were prepared, NMFS had only 2 years of observer data available to estimate mean annual mortality subsequent to the implementation of the Plan. By including the 1999 observer data to calculate the mean annual mortality for the fishery, NMFS is using the best scientific information available to estimate mortality under the Plan. NMFS agrees that 5 years of data collected under the Plan will provide a greater precision for the mortality estimate. In addition, NMFS believes that a 20-percent observer coverage is sufficient to provide an appropriate level of accuracy for calculating overall mortality estimates.

Comment 9: One commenter indicated that, because the use of pingers is one of the primary measures for reducing take under the Plan, NMFS should include the observed sperm whale that was entangled in 1996, before the implementation of the Plan, because pingers were attached to the net during the set.

Response: NMFS disagrees. Although the sperm whale was taken in a set in which pingers were attached, the pingerconfiguration did not comply with the Plan. Under the Plan, a net 1,000 fathoms long is required to have 41 pingers attached alternating between the floatline and the leadline, spaced 300 feet (50 fathoms) apart. The sperm whale observed taken in 1996 was in a set in which the net had only 33 pingers attached. Moreover, the SRG recommended that using 1997 and 1998 data would be most appropriate because the data would most accurately reflect entanglement rates after the changes in the fishery imposed by the Plan, even though the data are inconclusive about whether pingers affect sperm whale entanglement rates. The group agreed the same 2-year mortality averaging should be applied consistently in estimating mean annual mortality for all species incidentally taken in the CA/OR drift gillnet fishery when preparing the 2000 Marine Mammal SAR.

Comment 10: One commenter felt that because calendar year 1996 had 12.4-percent observer coverage, the estimated incidental take of sperm whales in 1996 should be 8. Using this assumption, the commenter calculated the mean annual take level for calendar years 1997, 1998, and 1999, to be 3.25, which is greater than the PBR level of two animals per year in the 2000 draft U.S. Pacific Marine Mammal SAR.

Response: NMFS disagrees. During the last 5 months (August through December) of 1996, NMFS’s observer program conducted a pinger experiment. As part of the experiment, sets were randomly selected to have pingers attached to the floatline and leadline of the net. Because only vessels that carried an observer participated in the experiment, mortality estimation for the fleet was based on the number of observed sets that did not have pingers attached to the net. The number of observed sets without pingers attached to the net used for estimation was 275, which represents overall fleet observer coverage of 8.5 percent. Mortality observed for sets using pingers was treated as a constant and added to estimates of mortality for sets not using pingers. Estimates were determined in this way because preliminary results indicated use of pingers may decrease cetacean entanglement. If a species was taken in sets deployed with pingers, but not in sets without pingers, the resultant mortality was a constant without an associated standard error such as the single sperm whale entanglement. For this reason, the sperm whale estimated mortality in 1996 was one, rather than eight, as suggested by the commenter.

Comment 11: One commenter questioned whether a permit could be issued under section 101(a)(5)(E) of the MMPA because there is insufficient evidence to support NMFS’ determination that the California/Oregon/Washington sperm whale stock is stable because of the uncertainty of the data.

Response: NMFS disagrees. Although the draft 2000 U.S. Pacific Marine Mammal SAR does not explicitly state that the population is stable or increasing, the report indicates that the California/Oregon/Washington sperm whale population has been variable possibly because sperm whale distribution in these waters may vary annually. This variability does not mean that the population is decreasing, but rather the trend is not obvious. In addition, there is evidence that indicates the sperm whale population abundance estimate is an underestimate of true abundance because recent studies suggest sperm whale group sizes may have been underestimated on past line-transect surveys. Furthermore, because a recovery factor of 0.1 is used for the California/Oregon/Washington sperm whale stock, a proportion of the expected net production is allocated towards population growth and compensates for uncertainties that might prevent population recovery, such as biases in the estimation of the minimum population size and maximum growth rates, or errors in the determination of stock structure. Therefore, the uncertainty in the abundance estimate is considered when calculating the PBR value.

Comment 12: One commenter questioned whether a permit could be issued before a sperm whale recovery plan has been circulated for public review.

Response: Section 101(a)(5)(E) of the MMPA requires that “a recovery plan has been developed or is being developed.” There currently is a recovery plan being developed for the sperm whale although the draft has not been finalized yet or circulated for public review.

Comment 13: One commenter questioned the incidental take calculations derived for the humpback whale because the calculations do not include take estimates for the California salmon troll fishery or for the Mexican fisheries.

Response: Under section 101(a)(5)(E), NMFS is required to determine whether the incidental mortality and serious injury by commercial fisheries will have a negligible impact on a species or stock listed as threatened or endangered under the ESA. In analyzing the impact of commercial fisheries on humpback whales, NMFS did not include the humpback whale snagged by a central California salmon troller because the interaction was classified as an injury, rather than a serious injury or mortality. In addition, because the California/Oregon/Washington - Mexico humpback whale stock spends approximately half of its time outside the U.S. EEZ (Mexican waters), the PBR for U.S. waters is only half of the overall PBR for the stock, which is intended to account for the amount of time the stock spends outside the U.S. exclusive economic zone (EEZ). For management purposes, NMFS calculates PBR values and mortality estimates for trans-boundary stocks based on the fraction of time in U.S. waters and the mortality estimate based on the calculated estimate of the stock residing in U.S. waters.

Comment 14: One commenter questioned whether a permit should be issued for fin whales because the estimated mean annual mortality is greater than the PBR value reported in the 1996 U.S. Pacific Marine Mammal SAR.

Response: NMFS did not use the PBR value reported in the 1996 U.S. Pacific Marine Mammal SAR because the most recent PBR information is in the draft 2000 U.S. Pacific Marine Mammal SAR. Using a 3-year average (1997, 1998, 1999), the mean annual estimated mortality for fin whales (1.7) is less than the PBR level (2.1) in the draft 2000 U.S. Pacific Marine Mammal SAR.

Comment 15: One commenter questioned whether a permit should be issued if the mean annual take (1997-1999) of the fin whales may be greater than the PBR value reported in the 2000 U.S. Pacific Marine Mammal SAR.

Response: Although the estimated mortality level in the SAR is near the PBR level for the fin whale stock, NMFS had determined that the history of mortality of fin whales incidental to the driftnet fishery has had a negligible impact on the fishery. The other conditions regarding the issuance of the permit have been satisfied; therefore, NMFS must issue the permit.

The negligible impact determination was based upon the 10-year history of the observer program in the fishery. The take observed in 1999 was the only observed mortality during that period. Consequently, NMFS determined that the fishery had a remote likelihood of taking fin whales on an annual basis, which would result in a negligible impact.

The mortality estimate in the SAR was based upon 3 years of data, which is the period that the fishery has been under a take reduction plan. There is no reason to believe that the conservation measures included in the plan (lowered head rope and pinger-equipped nets)would make the nets more likely to take a fin whale. Therefore, using the 10-year history of observer data in the fishery was appropriate for use in the negligible impact determination.

Comment 16: One commenter stated that a permit should not be issued to the CA/OR drift gillnet fishery for the taking of fin whales because mortality from the Mexican drift gillnet fishery was not considered when calculating the estimated mortality from all commercial fisheries.

Response: NMFS disagrees. The fin whale that was taken by the CA/OR drift gillnet fishery was from the California/Oregon/Washington fin whale stock. For management purposes, this stock does not include animals of the Mexican fin whale stock because there is insufficient information at this time to conclude that the fin whale population that increases seasonally in winter and spring in the Gulf of California is part of the California/Oregon/Washington fin whale stock.

Comment 17: One commenter stated that a permit should not be issued to the CA/OR drift gillnet fishery for the take of fin whales because mortality from ship strikes was not considered when calculating the estimated mortality from all commercial fisheries.

Response: NMFS disagrees. Under section 101(a)(5)(E) of the MMPA, NMFS must determine whether the incidental mortality and serious injury from commercial fisheries will have a negligible impact on such species or stock. For purposes of issuing a permit, NMFS is not required to consider mortality caused by ship strikes.

Comment 18: One commenter stated that a permit may not be issued unless a full and proper National Environmental Policy Act (NEPA) analysis is completed.

Response: NMFS agrees. An EA was prepared for this permit.

Comment 19: One commenter requested that NMFS significantly increase observer coverage levels for the CA/OR drift gillnet fishery as a condition of any future federal authorizations because the incidental take analysis is highly speculative.

Response: NMFS believes that 20-percent observer coverage is sufficient to calculate reliable mortality estimates for species listed under the MMPA and the ESA even though entanglement events are rare. For this reason, NMFS does not intend to require additional observer coverage as a condition of issuing a permit under section 101(a)(5)(E) of the MMPA.

Summary of Findings

NMFS has evaluated the best available information for the four stocks listed as threatened or endangered under the ESA addressed by this permit and has determined, on a stock-by-stock basis, whether the mortality and serious injury (using 3-year averages 1997, 1998, 1999) incidental to the CA/OR drift gillnet fishery is having a negligible impact on such stocks (NMFS, 2000). Based on this assessment, NMFS concludes that the estimated mortality and serious injury caused by the CA/OR drift gillnet fishery would cause no more than a 10-percent increase in the time to recovery for each of the four stocks of marine mammals addressed by this permit and is, therefore, negligible.

These stocks were then reviewed to confirm that: (1) a recovery plan has been developed or is being developed, and (2) where required under section 118 of the MMPA, a monitoring program has been established, vessels engaged in such fisheries are registered, and a take reduction plan has been, or is being, developed.

For the following stocks with documented evidence of fishery-related interactions, NMFS has determined that the mortality and serious injury incidental to the CA/OR drift gillnet fishery will have a negligible impact and issues a permit for incidental takes of:

(1) Fin whale, California/Oregon/Washington stock;

(2) Humpback whale, California/Oregon/Washington-Mexico stock;

(3) Steller sea lion, eastern stock; and

(4) Sperm whale, California/Oregon/Washington stock.

A stock-by-stock summary of the negligible impact determination follows.

Fin whale, California/Oregon/Washington stock: The PBR for this stock is 2.1 whales per year. After the 1997 implementation of the Plan, overall cetacean entanglement rates in the CA/OR drift gillnet fishery dropped considerably. Using a 3-year (1997-1999) average, the annual mean mortality and serious injury rate from the CA/OR drift gillnet fishery is estimated to be 1.7. In addition, during the past 10 years, only one fin whale has been observed taken in this fishery, indicating a remote likelihood of a fin whale take in the CA/OR drift gillnet fishery.

Humpback whale, California/Oregon/Washington-Mexico stock: The PBR level for this stock is 1.7 whales per year. Using a 3-year average (1997-1999), the mean annual mortality and serious injury rate from the CA/OR drift gillnet fishery is estimated to be 0.0 humpback whales. One observed humpback whale entanglement in 1999 was released alive without any trailing gear and was not considered a serious injury or mortality. Since the beginning of the observer program in 1990, there have been no reported mortalities or serious injuries of humpback whales.

Steller sea lion, eastern stock: The PBR level for this stock is 1,368 animals per year. Fishery observers monitored the CA/OR drift gillnet fishery between 1990 and 1999. In both 1992 and 1994, one Steller sea lion mortality was observed incidental to this fishery. Using a 3-year average (1997-1999), the mean annual mortality and serious injury rate from the CA/OR drift gillnet fishery is estimated to be 0.0 animals for the CA/OR drift gillnet fishery.

Sperm whale, California/Oregon/Washington stock: The PBR level for this stock is 2.0 whales per year. In 1998, one sperm whale was observed killed in a net that was not in compliance with the Plan. Using a 3-year average (1997-1999), the mean annual mortality and serious injury rate from the CA/OR drift gillnet fishery is estimated to be 1.7 sperm whales. The Team recommended no further strategies to reduce sperm whale entanglement be taken until the effectiveness of pingers is better understood. At the recommendation of the Team, NMFS conducted workshops to educate vessel operators on the need to use the full complement of pingers required by the Plan. NMFS enforcement also trained the U.S. Coast Guard about the requirements of the Plan and requested their assistance with at-sea enforcement.

NMFS prepared an EA on the final rule to implement the Plan (62 FR 51805, October 3, 1997). That EA has been reissued and modified to include the effects of: (1) issuance of this permit, (2) additional species of sea turtles and marine mammals, (3) minor changes to the Plan.

Issuance of Permits

Based on requirements of section 101(a)(5)(E) of the MMPA, NMFS is issuing a permit to allow the incidental, but not intentional, taking of four stocks of endangered or threatened marine mammals to the CA/OR drift gillnet fishery: (1) fin whale, California/Oregon/Washington stock; (2) humpback whale, California/Oregon/Washington-Mexico stock; (3) Steller sea lion, eastern stock; and (4) sperm whale, California/Oregon/Washington stock. These permits may be suspended or revoked if the level of take is likely to result in an impact that is more than negligible.

References

Barlow, J., S. Swartz, T. Eagle, and P. Wade. 1995. U.S. Marine Mammal Stock Assessments: Guidelines for Preparation, Background, and a Summary of the 1995 Assessments. U.S. Department of Commerce, NOAA Technical Memorandum NMFS-SWFSC-219. 162 p.

Cameron, G.A., and K.A. Forney. 2000. Preliminary Estimates of Cetacean Mortality in California/Oregon Gillnet Fisheries for 1999. Intl. Whal. Comm. Working paper. SC/52/024.

National Marine Fisheries Service. 2000. Assessment for Issuing a Permit Under Section 101(a)(5)(E) of the Marine Mammal Protection Act to the California/Oregon Drift Gillnet Fishery. Southwest Region, Protected Resources Division.

Dated: October 24, 2000. Donald R. Knowles,

Director, Office of Protected Resources, National Marine Fisheries Service.

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