Small Takes of Marine Mammals Incidental to Specified Activities; Harbor Activities at Vandenberg Air Force Base, CA

AGENCY:

National Marine Fisheries Service (NMFS), National Oceanic and Atmospheric Administration (NOAA), Commerce.

ACTION:

Notice of receipt of application and proposed authorization for incidental harassment of marine mammals; request for comments.

SUMMARY:

NMFS has received a request from The Boeing Company (Boeing) for an authorization to take small numbers of marine mammals by harassment incidental to harbor activities related to the Delta IV/Evolved Expendable Launch Vehicle (EELV) at south Vandenberg Air Force Base, CA (VAFB). Under the Marine Mammal Protection Act (MMPA), NMFS is requesting comments on its proposal to authorize Boeing to take, by harassment, small numbers of several species of pinnipeds at south VAFB beginning in May 2003.

DATES:

Comments and information must be received no later than May 9, 2003.

ADDRESSES:

Comments on the application should be addressed to Chief, Marine Mammal Conservation Division, Office of Protected Resources, NMFS, 1315 East-West Highway, Silver Spring, MD 20910-3225. Comments will not be accepted if submitted via e-mail or the Internet. A copy of the application (which includes the list of references used in this document) may be obtained by writing to this address or by telephoning one of the contacts listed here.

FOR FURTHER INFORMATION CONTACT:

Kimberly Skrupky, (301) 713-2322, ext. 163 or Christina Fahy, (562) 980-4023.

SUPPLEMENTARY INFORMATION:

Background

Sections 101(a)(5)(A) and (D) of the MMPA (16 U.S.C. 1361 et seq.) direct the Secretary of Commerce to allow, upon request, the incidental, but not intentional taking of small numbers of marine mammals by U.S. citizens who engage in a specified activity (other than commercial fishing) within a specified geographical region if certain findings are made and either regulations are issued or, if the taking is limited to harassment, notice of a proposed authorization is provided to the public for review.

Permission for incidental takings may be granted if NMFS finds that the taking will have no more than a negligible impact on the species or stock(s) and will not have an unmitigable adverse impact on the availability of the species or stock(s) for subsistence uses and that the permissible methods of taking and requirements pertaining to the monitoring and reporting of such taking are set forth.

NMFS has defined “negligible impact” in 50 CFR 216.103 as:

an impact resulting from the specified activity that cannot be reasonably expected to, and is not reasonably likely to, adversely affect the species or stock through effects on annual rates of recruitment or survival.

Subsection 101(a)(5)(D) of the MMPA established an expedited process by which citizens of the United States can apply for an authorization to incidentally take small numbers of marine mammals by harassment. The MMPA defines “harassment” as:

any act of pursuit, torment, or annoyance which

Subsection 101(a)(5)(D) establishes a 45-day time limit for NMFS review of an application followed by a 30-day public notice and comment period on any proposed authorizations for the incidental harassment of small numbers of marine mammals. Within 45 days of the close of the comment period, NMFS must either issue or deny issuance of the authorization.

Summary of Request

On January 28, 2003, NMFS received an application from Boeing requesting an authorization for the harassment of small numbers of Pacific harbor seals (Phoca vitulina richardsi) and California sea lions (Zalophus californianus) incidental to harbor activities related to the Delta IV/EELV, including: transport vessel operations, cargo movement activities, harbor maintenance dredging, and kelp habitat mitigation operations. In addition, northern fur seals (Callorhinus ursinus) and northern elephant seals (Mirounga angustirostris) may also be incidentally harassed but in smaller numbers. An Incidental Harassment Authorization (IHA) was issued to Boeing on May 20, 2002 and remains in effect until May 20, 2003 (see FR 36151, May 23, 2002). The harbor where activities will take place is on south VAFB approximately 2.5 mi (4.02 km) south of Point Arguello, CA, and approximately 1 mi (1.61 km) north of the nearest marine mammal pupping site (i.e., Rocky Point).

Specified Activities

Delta Mariner off-loading operations and associated cargo movements will occur a maximum of 3 times per year, beginning December, 2003. The Delta Mariner is a 95.1-m (312-ft) long, 25.6-m (84-ft) wide steel hull ocean-going vessel capable of operating at a 2.4-m (8-ft) draft. For the first few visits to the south VAFB harbor, tug boats will accompany the Delta Mariner. Sources of noise from the Delta Mariner include ventilating propellers used for maneuvering into position and the cargo bay door when it becomes disengaged. Removal of the CBC from the Delta Mariner requires use of an elevating platform transporter. An additional source of noise with sound levels measured at a maximum of 82 dB A-weighted (re 20 microPascals at 1-m) 6.1 m (20 ft) from the engine exhaust (Acentech, 1998). Procedures require 2 short (approximately 1/3 second) beeps of the horn prior to starting the ignition. At 60.9 m (200 ft) away, the sound level of the EPT horn ranged from 62-70 dB A-weighted. Containers containing flight hardware items will be towed off the Delta Mariner by a tractor tug that generates a sound level of approximately 87 dB A-weighted at 15.2 m (50 ft) while in operational mode. Total time of Delta Mariner docking and cargo movement activities is estimated at between 14 and 18 hours in good weather.

To accommodate the Delta Mariner, the harbor will need to be dredged, removing approximately 3,000 to 5,000 cubic yards of sediment per dredging. Dredging will involve the use of heavy equipment, including a clamshell dredge, dredging crane, a small tug, dredging barge, dump trucks, and a skip loader. Measured sound levels from this equipment are roughly equivalent to those estimated for the wharf modification equipment: 61-81 dB A-weighted at 76.2 m (250 ft). Dredge operations, from set-up to tear-down, would continue 24-hours a day for 3-5 weeks. Sedimentation surveys have shown that initial dredging indicates that maintenance dredging should be required annually or twice per year, depending on the hardware delivery schedule.

A more detailed description of the work proposed for 2003 is contained in the application which is available upon request (see ADDRESSES) and in the Final US Air Force Environmental Assessment for Harbor Activities Associated with the Delta IV Program at Vandenberg Air Force Base (ENSR International, 2001).

Habitat and Marine Mammals Affected by the Activity

The marine mammal species likely to be harassed incidental to harbor activities at south VAFB are the Pacific harbor seal and the California sea lion. The most recent estimate of the Pacific harbor seal population in California is 30,293 seals (Forney et al., 2000). From 1979 to 1995, the California population increased at an estimated annual rate of 5.6 percent. The total population of harbor seals on VAFB is now estimated to be 1,040 (775 on south VAFB) based on sighting surveys and telemetry data (SRS Technologies, 2001).

The daily haul-out behavior of harbor seals along the south VAFB coastline is dependent on time of day rather than tide height. The highest number of seals haul-out at south VAFB between 1100 through 1700 hours. In addition, haul-out behavior at all sites seems to be influenced by environmental factors such as high swell, tide height, and wind. The combination of all three may prevent seals from hauling out at most sites. The number of seals hauled out at any site can vary greatly from day to day based on environmental conditions. Harbor seals occasionally haul out at a beach 76.2 m (250 ft) west of the south VAFB harbor and on rocks outside the harbor breakwater where Boeing will be conducting Delta Mariner operations, cargo loading, dredging activities, and reef enhancement activities. The maximum number of seals present during past dredging of the harbor was 43, with an average of 21 seals sighted per day. The harbor seal pupping site closest to south VAFB harbor is at Rocky Point, approximately 1.6 km (1 mi) north.

Several factors affect the seasonal haul-out behavior of harbor seals including environmental conditions, reproduction, and molting. Harbor seal numbers at VAFB begin to increase in March during the pupping season (March to June) as females spend more time on shore nursing pups. The number of hauled-out seals is at its highest during the molt which occurs from May through July. During the molting season, tagged harbor seals at VAFB increased their time spent on shore by 22.4 percent; however, all seals continued to make daily trips to sea to forage. Molting harbor seals entering the water because of a disturbance are not adversely affected in their ability to molt and do not endure thermoregulatory stress. During pupping and molting season, harbor seals at the south VAFB sites expand into haul-out areas that are not used the rest of the year. The number of seals hauled out begins to decrease in August after the molt is complete and reaches the lowest number in late fall and early winter.

During the wharf modification activity in June-July 2002, California sea lions were observed hauling out in small numbers. Although this is considered to be an unusual occurrence and is possibly related to fish schooling in the area, Boeing included sea lions in their request.

California sea lions range from British Columbia to Mexico. The minimum U.S. population estimate for California sea lions is 109,854 individuals. Since 1983, the population has grown at a rate of 5.0-6.2 percent annually. A 1985-1987 population survey indicated that most individuals on the Northern Channel Islands were on San Miguel Island, with the population ranging from 2,235 to over 17,000. The largest numbers of California sea lions in the VAFB vicinity occur at Lion Rock, 0.4 mi (0.64 km) southeast of Point Sal. This area is approximately 1.5 mi (2.41 km) north of the VAFB boundary. At least 100 sea lions can be observed during any season at this site. The Point Arguello beaches and the rocky ledges of South Rocky Point on south VAFB are haulout areas that may be used by California sea lions. The maximum number of sea lions seen hauling out during the recent wharf modification was six, daily counts ranging from 1 to 6 animals.

During the breeding season, most of California sea lions inhabit southern California and Mexico. Rookery sites in southern California are limited to San Miguel Island and to the southerly Channel Islands of San Nicolas, Santa Barbara, and San Clemente. Breeding season begins in mid-May, occurring within 10 days of arrival at the rookeries. Molting occurs gradually over several months in the late summer and fall. Because the molt is not catastrophic, the sea lions can enter the water to feed.

Male California sea lions migrate annually. In the spring they migrate southward to breeding rookeries in the Channel Islands and Mexico, then migrate northward in the late summer following breeding season. Females appear to remain near the breeding rookeries. The greatest population on land occurs in September and October during the post-breeding dispersal and although many of the sea lions, particularly juveniles and sub-adult and adult males, may move north away from the Channel Islands.

Small groups of sea lions have been observed heading south along the VAFB coastline each year in April and May. In August, large groups of 25 to over 300 sea lions can be seen migrating north. Hauled out juvenile sea lions, as well as harbor seals, can be observed along the South Base sites in July, August, and September. Starving and exhausted subadult sea lions are also fairly common on the central California beaches during July and August.

Other marine mammal species are known to occur infrequently along the south VAFB coast during certain times of the year and are unlikely to be harassed by Boeing's activities. These four species are: the northern elephant seal, the northern fur seal, Guadalupe fur seal (Arctocephalus townsendi), and Steller sea lions (Eumetopias jubatus). Northern elephant seals may occur on VAFB but do not haul out in the harbor area. Northern fur seals, Guadalupe fur seals, and Steller sea lions occur along the California coast and Northern Channel Islands but are not likely to be found on VAFB. Descriptions of the biology and local distribution of these species can be found in the application as well as other sources such as Stewart and Yochem (1994, 1984), Forney et al. (2000), Koski et al. (1998), Barlow et al. (1993), Stewart and DeLong (1995), and Lowry et al. (1992). NMFS Stock Assessments can be viewed at: http://www.NMFS.noaa.gov/pr/PR2/

Stock_Assessment_Program/sars.html. Please refer to those documents for information on these species.

Potential Effects of Activities on Marine Mammals

Acoustic and visual stimuli generated by the use of heavy equipment during the Delta Mariner and off-loading operations, dredging, and kelp habitat mitigation, as well as the increased presence of personnel, may cause short-term disturbance to harbor seals and California sea lions hauled out along the beach and rocks in the vicinity of the south VAFB harbor. This disturbance from acoustic and visual stimuli is the principal means of marine mammal taking associated with these activities. Based on the measured sounds of construction equipment, such as might be used during Boeing's activities, sound levels from all equipment drop to a maximum level of 95 dB A-weighted within 50 ft (15.2 m) of the sources. In contrast, the ambient background noise measured approximately 76.2 m (250 ft) from the beach was estimated to be 35-48 dB A-weighted (Acentech, 1998; EPA, 1971).

Pinnipeds sometimes show startle reactions when exposed to sudden brief sounds. An acoustic stimulus with sudden onset (such as a sonic boom) may be analogous to a “looming” visual stimulus (Hayes and Saif, 1967), which may elicit flight away from the source (Berrens et al., 1988). The onset of operations by a loud sound source, such as the elevating platform transporter during CBC off-loading procedures, may elicit such a reaction. In addition, the movements of cranes and dredges may represent a “looming” visual stimulus to seals hauled out in close proximity. Seals and sea lions exposed to such acoustic and visual stimuli may either exhibit a startle response and/or leave the haul-out site.

According to the MMPA, if harbor activities disrupt the behavioral patterns of harbor seals, these activities would take marine mammals by Level B harassment. In general, if the received level of the noise stimulus exceeds both the background (ambient) noise level and the auditory threshold of the animals, and especially if the stimulus is novel to them, there may be a behavioral response. The probability and degree of response will also depend on the season, the group composition of the pinnipeds, and the type of activity in which they are engaged. Minor and brief responses, such as short-duration startle or alert reactions, are not likely to result in disruption of behavioral patterns, such as migration, nursing, breeding, feeding, or sheltering (i.e., Level B harassment) and would not cause serious injury or mortality to marine mammals.

On the other hand, startle and alert reactions accompanied by large-scale movements, such as stampedes into the water, could resul in injury of individuals and would be considered a take by harassment. In addition, such large-scale movements by dense aggregations of marine mammals or on pupping sites could potentially lead to takes by serious injury or death. However, there is no potential for large-scale movements leading to serious injury or mortality near the south VAFB harbor, because on average the number of harbor seals hauled out near the site on average is less than 30 and there is no pupping at nearby sites. The effects of the harbor activities are expected to be limited to short-term startle responses and localized behavioral changes.

For a further discussion of the anticipated effects of the planned activities on harbor seals in the area, please refer to the application and ENSR International's 2001 Final Environmental Assessment. Information in the application and referenced sources is preliminarily adopted by NMFS as the best information available on this subject.

Numbers of Marine Mammals Expected to Be Harassed

Boeing estimates that a maximum of 43 harbor seals per day may be hauled out near the south VAFB harbor, with a daily average of 21 seals sighted when tidal conditions were favorable during previous dredging operations in the harbor. Considering the maximum and average number of seals hauled out per day, assuming that the seals may be seen more than once, and using a maximum total of 83 operating days in 2003-2004, NMFS estimates that 145 to 623 Pacific harbor seals may be subject to Level B harassment, as defined in 50 CFR 216.3.

During wharf modification activities, a maximum of six California sea lions were seen hauling out in a single day, averaging between one and six sea lions each day. Based on its own calculations, NMFS believes that a total of 100 California sea lions, 10 northern elephant seals, and 5 northern fur seals may be subject to Level B harassment, as defined in 50 CFR 216.3, because they may be in nearby waters.

Possible Effects of Activities on Marine Mammal Habitat

Boeing anticipates no loss or modification to the habitat used by Pacific harbor seals or California sea lions that haul out near the south VAFB harbor. The harbor seal and sea lion haul-out sites near south VAFB harbor are not used as breeding, molting, or mating sites; therefore, it is not expected that the activities in the harbor will have any impact on the ability of Pacific harbor seals or California sea lions in the area to reproduce.

Boeing does anticipate unavoidable kelp removal during dredging. This habitat modification will not affect the marine mammal habitat. However, Boeing will mitigate for the removal of kelp habitat by placing 150 tons of rocky substrate in a sandy area between the breakwater and the mooring dolphins to enhance an existing artificial reef. This type of mitigation was implemented by the Army Corps of Engineers following the 1984 and 1989 dredging. A lush kelp bed adjacent to the sandy area has developed from the efforts. The substrate will consist of approximately 150 sharp-faced boulders, each with a diameter of about 2 ft (0.61 m) and each weighing about one ton. The boulders will be brought in by truck from an off-site quarry and loaded by crane onto a small barge at the wharf. The barge is towed by a tugboat to a location along the mooring dolphins from which a small barge-mounted crane can place them into the sandy area. Boeing plans to perform the reef enhancement in conjunction with the next maintenance dredging event in order to minimize cost and disturbances to animals. Noise will be generated by the trucks delivering the boulders to the harbor and during the operation of unloading the boulders onto the barges and into the water.

Possible Effects of Activities on Subsistence Needs

There are no subsistence uses for Pacific harbor seals in California waters, and, thus, there are no anticipated effects on subsistence needs.

Mitigation

To reduce the potential for disturbance from visual and acoustic stimuli associated with the activities Boeing will undertake the following marine mammal mitigating measures:

(1) If activities occur during nighttime hours, lighting will be turned on before dusk and left on the entire night to avoid startling harbor seals at night.

(2) Activities should be initiated before dusk.

(3) Construction noises must be kept constant (i.e., not interrupted by periods of quiet in excess of 30 minutes) while harbor seals are present.

(4) If activities cease for longer than 30 minutes and harbor seals are in the area, start-up of activities will include a gradual increase in noise levels.

(5) A qualified marine mammal observer will visually monitor the harbor seals on the beach adjacent to the harbor and on rocks for any flushing or other behaviors as a result of Boeing's activities. If flushing results, then the activities suspected of causing the seals to enter the water will be delayed until the seals leave the area.

(6) The Delta Mariner and accompanying vessels will enter the harbor only when the tide is too high for harbor seals to haul-out on the rocks and the vessel will reduce speed 1.5 to 2 knots once the vessel is within 3 mi (4.83 km) of the harbor. The vessel will enter the harbor stern first, approaching the wharf and dolphins at less than 0.75 knot.

(7) As alternate dredge methods are explored, the dredge contractor may introduce quieter techniques and equipment.

Monitoring

As part of its 2002 application, Boeing provided a proposed monitoring plan for assessing impacts to harbor seals from the activities at south VAFB harbor and for determining when mitigation measures should be employed.

A NMFS-approved and VAFB-designated biologically trained observer will monitor the area for pinnipeds during all harbor activities. During nighttime activities, the harbor area will be illuminated, and the monitor will use a night vision scope. Monitoring activities will consist of:

(1) Conducting baseline observation of pinnipeds in the project area prior to initiating project activities.

(2) Conducting and recording observations on pinnipeds in the vicinity of the harbor for the duration of the activity occurring when tides are low enough for pinnipeds to haul out (2 ft, 0.61 m, or less).

(3) Conducting post-construction observations of pinniped haul-outs in the project area to determine whether animals disturbed by the project activities return to the haul-out.

Reporting

Boeing will notify NMFS 2 weeks prior to initiation of each activity. After each activity is completed, Boeing will provide a report to NMFS within 90 days. This report will provide dates and locations of specific activities, details of seal behavioral observations, and estimates of the amount and nature of all takes of seals by harassment or in other ways. In addition, the report will include information on the weather, the tidal state, the horizontal visibility, and the composition (species, gender, and age class) and locations of haul-out group(s). In the unanticipated event that any cases of pinniped injury or mortality are judged to result from these activities, this will be reported to NMFS immediately.

Consultation

Under section 7 of the Endangered Species Act, NMFS has begun consultation on the proposed issuance of an IHA. Consultation will be concluded prior to the issuance of an IHA.

Although sea otters are not within the jurisdiction of NMFS, VAFB formally consulted with U.S. Fish and Wildlife Service (FWS) in 1998 on the possible take of southern sea otters during Boeing's harbor activities at south VAFB. A Biological Opinion was issued in August 2001. Southern sea otters were discussed in these documents and FWS recognized that Boeing will restore sea otter habitat (i.e., kelp beds) in the vicinity of the harbor to replace kelp destroyed during dredging. In addition, the FWS noting that VAFB has committed to a southern sea otter monitoring program designed to detect the presence and possible disturbance at the VAFB harbor area during dredging activities.

NEPA

In accordance with section 6.01 of the National Oceanic and Atmospheric Administration (NOAA) Administrative Order 216-6 (Environmental Review Procedures for Implementing the National Environmental Policy Act, May 20, 1999), NMFS has determined based on the content and analysis of Boeing's request for an IHA, and the Final EA for Harbor Activities Associated with the Delta IV Program at VAFB (ENSRI, 2001) that the proposed issuance of this IHA to Boeing by NMFS will not individually or cumulatively result in a significant impact on the quality of the human environment as defined in 40 CFR 1508.27. Impacts are not expected to be outside the scope of that EA. Therefore, this action meets the definition of a “Categorical Exclusion” as defined under NOAA Administrative Order 216-6 and is exempted from further environmental review.

Preliminary Conclusions

NMFS proposes to issue an IHA to Boeing for harbor activities related to the Delta IV/EELV to take place at south VAFB over a 1-year period. The proposal to issue this IHA is contingent upon adherence upon the previously mentioned mitigation, monitoring, and reporting requirements. NMFS has preliminarily determined that the impact of harbor activities related to the Delta IV/EELV at VAFB, including: transport vessel operations, cargo movement activities, harbor maintenance dredging, and kelp habitat mitigation will result in the harassment of only small numbers of Pacific harbor seals and California sea lions; would have no more negligible impact on these marine mammal stocks,; and would not have an unmitigable adverse impact on the availability of marine mammal stocks for subsistence uses. While behavioral modifications may be made by these species to avoid the resultant acoustic and visual stimuli, there is no potential for large-scale movements, such as stampedes, since harbor seals and sea lions haul out in such small numbers near the site (maximum number of harbor seals hauled out in one day estimated at 43 seals, averaging at 21 seals per day, maximum number of sea lions hauled out in one day is estimated at six sea lions). The effects of the harbor activities are expected to be limited to short-term and localized behavioral changes. Therefore, NMFS preliminarily concludes that the effects of the planned demolition activities will have no more than a negligible impact on pinnipeds.

Due to the localized nature of these activities, the number of marine mammals potentially taken by harassment are estimated to be small. In addition, no take by injury and/or death is anticipated, and the potential for temporary or permanent hearing impairment is unlikely given the low noise levels and will be entirely avoided through the incorporation of appropriate mitigation measures. No rookeries, mating grounds, areas of concentrated feeding, or other areas of special significance for marine mammals occur within or near south VAFB harbor.

Information Solicited

NMFS requests interested persons to submit comments and information concerning this request (see ADDRESSES). Prior to submitting comments, NMFS recommends readers review NMFS' responses to those comments on this activity submitted previously (see 67 FR 63151, May 23, 2002).