Southern Resident Killer Whale Satellite Tagging
2 April update5 April – Final update – Since the morning of 28 March when K25 was near the Point Grenville area the whales moved north to the head of the Quinault Canyon. By 29 March the whales had turned south and were on the continental shelf break to the west of Gray's Harbor. The whales continued south and were southwest of the Astoria Canyon on 30 March. The whales then traveled to the east near the entrance of the Columbia River and by 31 March they were near the entrance of Grays Harbor. The whales again turned south and were in the Astoria Canyon on 1 April. The whales then turned east and then north traveling just offshore of the entrance to the Columbia River and were just northwest of Cape Disappointment on the morning of 2 April.
2 April update – Since the morning of 28 March when K25 was near the Point Grenville area the whales moved north to the head of the Quinault Canyon. By 29 March the whales had turned south and were on the continental shelf break to the west of Gray's Harbor. The whales continued south and were southwest of the Astoria Canyon on 30 March. The whales then traveled to the east near the entrance of the Columbia River and by 31 March they were near the entrance of Grays Harbor. The whales again turned south and were in the Astoria Canyon on 1 April. The whales then turned east and then north traveling just offshore of the entrance to the Columbia River and were just northwest of Cape Disappointment on the morning of 2 April.
28 March update – Since 25 March when K25 was off Willipa Bay the whales traveled as far south as Tillimook Head before reversing directions and gradually making their way north over the last two days reaching the Point Grenveille area this morning
25 March update – Over the past five days K25 has remained off the coast off southern Washington and northern Oregon. On the 20 March they were approaching the Astoria Canyon. On 21 March they went through the Astoria Canyon and traveled back north and were off the entrance to Grays Harbor on 22 March. They continued north and by the morning of the 23rd March were well to the northwest of Grays Harbor where they turned back south. By the morning of 24 March they were off the northern Oregon coast west of Cape Falcon. The whales then turned north and where off the entrance to Willipa Bay on the morning of the 25th
20 March update – Over the past two days K25 headed south along the Washington Coast. They were initially near the Juan de Fuca Canyon and moved south on the continental shelf and were approaching the Astoria Canyon this morning.
18 March update – Over the past four days K25 (and likely the rest of K pod) moved north up the Washington Coast. They remained off the Columbia River on 15 March, where they had been for the past several days, before starting the northbound transit which found them off the Westport area on the 16th, the northern Washington coast on the 17th, and by the morning of the 18th they had moved west off the continental shelf into over a 1000m of water.
14 March update – K25 (and likely the rest of K pod) have spent the last two days off the mouth of the Columbia River.
12 March update – K25 continued south from Cape Flattery on 11 March and the whales were off the mouth of the Columbia River on the 12 March.
10 March update – We caught up with K and L pods moving northbound off Destruction Island on the morning of 9 March and were again able to spend the day conducting prey and fecal sampling from our small boat based off the Bell M. Shimada. The whales foraged extensively which resulted in us being able to collect 11 prey samples today. The whales turned around at Cape Flattery that evening and headed south and moved through the same general area again on Sunday.
We concluded our research cruise on the Bell M. Shimada prematurely due to the budget sequestration on 9 March and returned to Newport, Oregon on Sunday 10 March.
We have received no further transmissions from the tag that was deployed on L88 after 0730 on Sunday 10 March and based on our observations of the tag attachment condition on 9 March it is likely this was due to detachment.
8 March update – Since 6 March we have continued to try to follow K and L pods on the NOAA vessel Bell M. Shimada. On the evening of 6 March the whales were offshore of Cape Elizabeth, Washington, heading southwest. By the morning of the 7th they were nearshore off the entrance of Willipa Bay before turning northwest. We spent the day following them in our small boat and collected several fecal samples. By this morning the whales were off the head of Gray's Canyon. The whales then moved inshore and were off of Gray's Harbor and northbound up the coast this evening.
In the process of trying to resight K and L pods this morning we inadvertently ran into 30-40 offshore type killer whales. We worked with Cascadia Research Collective staff that were there surveying the area for fin whales to photo-ID, deploy satillite-linked tags and collect other data on these whales.
6 March update – Since the previous update on 4 March when the NOAA vessel Bell M. Shimada was with K and L pods off Cannon Beach, Oregon, we have continued to follow them almost continuously up the Washington coast. They reached the northernmost point of their most recent round-trip to California this afternoon offshore of Cape Elizabeth, Washington before turning southwest and heading more offshore. We have been able to conduct small boat operations with the whales for the last two days and have been able to collect 3 prey samples and 7 fecal samples.
4 March update – On 2 March staff from the NWFSC, Cascadia Research Collective, and Biowaves, on the NOAA vessel Bell M. Shimada, intercepted K pod off Cape Blanco using location data from its satellite-linked tag. L pod was also present and a tag like the one on K25 was deployed on L88. These tags have allowed us to remain with these two pods almost continuously for the last 3 days as the whales have made their way up the Oregon coast. As of this afternoon they were off Cannon Beach, Oregon.
1 March update – Since 26 February when the whales were just south of Pt. Arena they have continued traveling north and were off Brookings, Oregon this morning. Staff from the NWFSC, Cascadia Research Collective, and Biowaves, will depart this afternoon from Newport, Oregon on the NOAA vessel Bell M. Shimada and attempt to locate K pod tomorrow.
28 February update –
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26 February update – In the last 4 days the whales traveled south from Trinidad Head to just south of Pt. Reyes yesterday morning before turning around and heading north. They were just south of Pt. Arena this afternoon. The transmitter began transmitting every day as of February 25th. Staff from the NWFSC, Cascadia Research Collective, and Biowaves, will attempt to locate K25 from the NOAA vessel Bell M. Shimada later this week.
22 February Update – In the last 2 days K25 traveled north from near Shelter Cove, California to the area just south of Crescent City before turning south and being off Trinidad Head this morning.
20 February Update – In the last 4 days K25 traveled south from near Shelter Cove, California to just north of Pt. Reyes before turning back north and traveling back to the the area off Shelter Cove today.
16 February Update – In the last 2 days K25 traveled south from the continental slope edge southwest of Crescent City to just north of Shelter Cove, California.
14 February Update – The previous location on 12 February found the whales just north of Eureka, California. In the last 2 days they traveled only as far south as Eureka before turning around and traveling to just north of Brookings, Oregon and turning south again with the last locations showing them traveling offshore to the continental slope edge southwest of Crescent City. Unfortunately inclement weather has continued prevented small boat response or resighting from shore.
12 February Update – On 10 February the whales were off Eureka, California. In the last 2 days they traveled only as far south as Cape Mendicino before turning north and then traveling as far north as Crescent City. By this morning they had turned south and were again were just north of Eureka. Unfortunately inclement weather has prevented small boat response or resighting from shore.
10 February Update – On the previous update on 8 February the whales were just north of Coos Bay, Oregon. By this morning they had traveled at an average speed of almost to 6 kts to a few miles offshore of Eureka, California. The most recent locations this morning suggest that the whales may have halted their southbound transit.
8 February Update – The previous update on 4 February found the whales at the base of the Juan de Fuca Canyon with a hint that they were turning south. By 6 February the whales had moved south to just southwest of the entrance to the Columbia River and by this morning they had continued south to just north of Coos Bay, Oregon.
4 February Update – As of 2 February K pod was off the continental shelf break between Willipa and Grays Harbors. By 4 February they had traveled up the shelf break to the base of the Juan de Fuca Canyon
2 February Update – As of 31 January K pod off of Cascade Head, Ore. This was likely close to the southernmost extent of this transit down the coast as on 2 February they had traveled back up to continental shelf break between Willipa and Grays Harbors.
29 January Update – As of today K25 has been tagged for one month and has provided significant new detailed information on the movements of K pod in the winter. As of 25 January K pod was traveling south along the Washington Coast and over the last 4 days continued south to about the Astoria Canyon before turning north. As this morning they were west of Gray's Harbor. It is important to note that given the tag is now transmitting every other day the connections of the some points on the map will not fully reflect the whale's movements.
26 January update – Prior to the deployment of the satellite-linked tag on K25 on 29 December 2012, we had pre-programed it to transmit on specific days and times of day in order to extend transmission life should the deployment extend beyond the average of 30 days we typically see for killer whales. There were no transmissions this morning as this was the first day that the tag was expected to go from an every day to an every other day transmission schedule. The last time we observed K25, on 17 January, off the southern Oregon coast, the tag attachment looked secure so we do not expect that the tag has detached. The map shows the movements from 24 January through 25 January as K pod traveled south along the Washington Coast.
24 January Update – Since 21 January when the whales were off LaPush, they continued northwest to near the Barkley Canyon off the southwest coast of Vancouver Island. They then reversed direction and headed into the Strait of Juan de Fuca yesterday morning, completing a round trip to California in just under 3 weeks. This morning they were located just west of cape Flattery near the Juan de Fuca Canyon.
21 January Update – Since 19 January the whales have continued traveling consistently north from Tillimook Head. They made a very interesting turn offshore at the Astoria Canyon and then followed the continental shelf break up to the Quinault Canyon before heading back in on the shelf. They were off LaPush this morning.
19 January Update – In the last two days the whales have continued traveling consistently north from Cape Blanco and were just south of Tillimook Head this morning. Jeff Jacobsen was able to intercept them on the water on Thursday when they passed Coos Bay and reports that they were very spread out and observed an attempted predation event when two whales were observed chasing a salmon near the surface.
17 January Update – Since the last update on 15 January the whales headed north from Crescent City and made it as far north as Cape Blanco before reversing course yesterday afternoon, traveling back to near Pt Orford, but were back off Cape Blanco this morning
15 January update – Since the last update on 13 January K pod has continued traveling north and as of 0945 AM today they were off Crescent City, California
13 January update – Since the previous update two days ago the whales traveled south from the Bodega Bay area and then reversed course off of Pt. Reyes and started heading north. They were 5 miles north of Pt Arena this morning. Today's map shows their movements since about 2000 on the 11th when they had reached the southernmost point in their travels down the coast.
11 January 2013 update – In the last two days K pod has continued traveling south, close to the coast, from off Eureka/Arcata to near Bodega Bay this morning. Yesterday, colleague Jodi Smith was able to get out on the water with the K pod with vessel support from California Department of Fish and Game and with Ken Balcomb on shore directing them to the whales.
9 January 2013 update – K pod off Eureka/Arcata California - In the last 3 days K pod traveled south from just north of Cape Blanco, Oregon to Eureka/Arcata California. Ken Balcomb from the Center for Whale Research was on site in Arcata yesterday and helped coordinate an on-water response by colleagues Jeff Jacobsen and Gary Friedrichsen that led to resighting the whales and collection of fish scales from a predation event and likely a fecal sample. The whales were still off Eureka/Arcata California this AM.
6 January 2013 Update -K pod continues down the Oregon coast - In the last two days K pod has traveled almost 3/4s of the way down the Oregon coast and was just south of Cape Arago, Oregon as of this morning.
5 January 2013 Update -K25 was tagged one week ago today and this map shows K pod's extensive movements during that time all the way from Puget Sound (the tagging location) down to about 25 miles south of Newport, Oregon as of this morning.
4 January 2013 Update - As of this morning, Friday, 4 January, K pod had continued traveling south and was off Tillimook Oregon. New map shows movements since Monday, 31 Dececember 2012.
3 January 2013 Update - Since the last update on 31 December 2012 when K25 was off Pt. Renfrew, Vancouver Island, he (and most likely the rest of K pod) has traveled south along the Washington coast and as of 8PM on Wednesday, January 2, 2013 was located near the Quinault Canyon. It was particularly interesting to see how close they traveled to the northern Washington coastline.
December 31, 2012 Update - As a continuation of a project began last year to help us understand where Southern resident killer whales go in the winter, and thus their winter habitat use, NWFSC researchers tagged an adult male, K25, in Puget Sound on December 29, 2012 with a satellite-linked tag. The information gathered from this tag will address the data gap in winter distribution identified in the Recovery Plan as well as provide information for improving Critical Habitat designation. This technique was recently identified as an important approach for addressing this issue by the independent science panel that assessed the impact of salmon fisheries on southern resident killer whales (http://www.nwr.noaa.gov/Marine-Mammals/Whales-Dolphins-Porpoise/Killer-Whales/ESA-Status/upload/KW-Chnk-final-rpt.pdf). The map below shows the most recently available track of K25 during tag deployment.
April 12, 2012, update - On March 26, 2012, researchers from Canada’s Department of Fisheries and Oceans encountered J pod off Nanaimo, BC, and obtained high resolution photos of the tag attachment site on the dorsal fin of J26. These photos were taken 32 days after the last transmission and show that the tag and darts are absent. A comparison of these recent photos with the images taken at the time of tagging has provided new insights into the relatively short (3 days) deployment. The images taken at the time of tagging indicated that the deployment appeared to be routine. However, comparison of these initial photos with recent photos suggests that the base of the tag was apparently not completely flush to the skin indicating that the darts did not fully implant, which may have been partly a function of the natural curvature of the fin, and a slightly skewed flight trajectory during deployment. Such an outcome is unusual, and these factors may have predisposed this tag to a shorter than expected attachment duration. The recent photos show two parallel and superficial indentations in the skin of the dorsal fin arching dorsally towards the front of the whale and appear to originate at the dart penetration sites. These indentations likely occurred when the tag was removed. While the mechanism for the tag removal remains unknown, it is possible that it was through interaction with another whale, and if the tag was not fully seated it would have been more prone to being easily dislodged.
The three day deployment on J26 was much shorter than the median duration of signal contact typically obtained for killer whales (29 days, n=30). While it is rare for a tag to detach after such a short period of time, it is important to note that the minimally invasive nature of the tag design allows for its relatively easy removal, as well as minimal tissue impacts and quick healing. There is no indication of swelling currently associated with the tag implant sites, and the tissue appears to be healing normally. We anticipate that normal healing will continue with none to minimal long-term consequence of tagging. We will continue to monitor the dorsal fin tissue condition of J26 until healing is complete.
March 2, 2012, update - The researchers continue their survey, with the primary goal of re-sighting J26. Although they have detected J pod on the towed acoustic array several times during the night, they have not yet encountered them during daylight hours. Other researchers from Canada’s Department of Fisheries and Oceans have reported an encounter with J pod in the Strait of Georgia late in the day on February 29. The Canadian researchers confirmed that the tag was detached from J26. The NWFSC is currently searching for J pod in that general area. We will continue efforts to resight J26 over the next several days and collect information on SKRW winter feeding activities. See the NOAA Ship Tracker website for the current location of the Bell M Shimada, where it has been searching over the last several days
On December 8, 2011, NOAA Fisheries’ Office of Protected Resources issued a scientific research permit amendment to the Northwest Fisheries Science Center (NWFSC) to authorize satellite tagging of up to six Southern Resident killer whales. On February 20, 2012, the first satellite tag was deployed on an adult male, J26, in the Strait of Juan de Fuca as part of a NWFSC research cruise on the NOAA ship Bell M. Shimada. Gaining additional information on winter habitat and prey of Southern Resident killer whales is an important part of the recovery plan for this endangered population. The map below illustrates the track of J26 over the first three days after tag deployment. Transmissions from the tag have not been obtained since the morning of February 23, probably due to loss of the tag or possibly due to a failure of the transmitter. The researchers will continue to visually and acoustically.
Locations of J26 from 6pm Feb 20 to 9am Feb 23.
What is the objective of satellite tagging southern resident killer whales?
NOAA Fisheries is mandated under the Endangered Species Act to develop a Recovery Plan for listed species, and completed a plan for Southern Resident Killer Whales (SRKW) in 2008. The Recovery Plan identifies the threats, data gaps, and research priorities for the population. One of the highest priorities identified for SRKW was to determine their coastal distribution in the winter. Although their summer range in inland waters is well defined, their coastal distribution, during the winter months, where they spend the vast majority of their time, is uncertain.
NMFS is also mandated to designate Critical Habitat for listed species. A prerequisite to Critical Habitat designation is determination of the area occupied by species and collection of location and habitat use data that are sufficient to determine “those physical and biological features that are essential to the conservation of a given species and that may require special management considerations or protection.” Habitat features may include, but are not limited to, the following: (1) space for individual and population growth, and for normal behavior; (2) food, or other nutritional or physiological requirements; (3) sites for breeding, reproduction, rearing of offspring; and generally; (4) habitats that are protected from disturbance or are representative of the historic geographical and ecological distributions of a species. The designation of Critical Habitat adds an increased threshold of protection under section 7 of the ESA. Once critical habitat is designated, section 7 of the ESA requires Federal agencies to ensure that they do not fund, authorize, or carry out any actions that will destroy or adversely modify that habitat. This is in addition to the requirement that Federal agencies ensure their actions do not jeopardize the continued existence of listed species. Examples of Federal actions that have been analyzed for impacts to SRKW critical habitat include fisheries regulations, in-water construction projects, wastewater treatment at Federal facilities, and issuance of scientific research permits. A 5-year review of the status of SRKW completed in 2011 recommended “Increasing knowledge of coastal distribution, habitat use, and prey consumption to inform critical habitat determination, identify any unknown threats, and assess and minimize impacts of ongoing and new coastal activities (i.e., fisheries, alternative energy projects).”
How might satellite tag-derived location data be used for Critical Habitat designation?
NMFS was able to partially designate Critical Habitat for SRKWs within the inland waters of Washington due to the very large data set (approximately 54,000 sighting reports collected over the last 20 years) from opportunistic sightings available from a long-term sighting network. However, the paucity of SRKW sighting data from the outer coast (less than 50 sightings over the past 20 years), combined with their wide-spread range, stretching from Monterey Bay, California, to the north end of the Queen Charlotte Islands, British Columbia, precluded NMFS from designating appropriate areas along the Pacific coast. Because there are so few locations over this long period, there are no discernible patterns of habitat use to allow for determination of essential features. Collection of movement data with satellite tags can provide spatially unbiased data over a short temporal scale to be able to assess occurrence and movement patterns that indicate specific areas of importance. Data from satellite tags can also fill in key data gaps, such as how far offshore the range of the SRKW extends, and data can direct studies, such as ship cruises, working to identify habitat features, including the specific prey the whales are eating in coastal waters.
An example of how satellite tagging information can help NMFS accomplish designating Critical Habitat in an effective manner was evidenced with Hawaiian Insular false killer whales. This small population is in the process of being listed under the ESA and a significant body of satellite tag location data has been obtained and was also used to inform the Critical Habitat designation process. NMFS has relied almost exclusively on this dataset from 23 satellite-tagged whales and is on track to designate Critical Habitat within the prescribed time limits mandated by the ESA. Although far fewer SRKWs will be tagged, we have found that a significant amount of new data can be gained from only a small number of tag deployments. An example of this is from recent tag deployments on a small number of Southeast Alaska resident-type whales. Like SRKW, despite extensive research efforts in the inland waters of Southeast Alaska and Prince William Sound, little was known of their coastal movements. With the deployment of only four tags to date, we have discovered that these whales range well to the west of Kodiak Island, which was completely unknown and this information will be important information to understanding their role in the Gulf of Alaska Ecosystem.
Why can’t SRKW occurrence and movements be determined using non-invasive approaches?
For the past seven years the NWFSC has actively used and supported (and will continue to support) several non-invasive approaches to assess the winter range of SRKW. Despite ongoing efforts to document the whales’ winter distribution through an enhanced coastal sighting network, deployment of autonomous acoustic recorders, and dedicated research cruises, a significant information gap remains in their spatial and temporal distribution which has precluded delineating coastal Critical Habitat. The coastal sighting network has yielded fewer than 20 sighting over the past six years. While these are valuable data and represent a significant increase compared to previous years, the three to four sightings gained per year do not provide sufficient data by themselves or in combination with other recently derived data to allow for Critical Habitat determination. Although SRKW have been located on four to five NWFSC killer whale-focused survey cruises, as well as on a few other cruises, like the sighting network data, these data are too limited to provide more than just isolated snapshots of the whales’ locations. Consequently, this hand full of sightings over the past seven years is insufficient to provide the data needed to fully assess essential habitat features, identify specific areas with those features, and designate additional Critical Habitat. While ocean-class vessel surveys offer the potential opportunity to follow the whales day and night to determine habitat use and possibly collect predation samples and feces for diet studies it is important to note that the NWFSC is typically only allocated 10-20 sea days per year on NOAA’s ocean class vessels. For the past two years the NWFSC has not been able to secure sea days due to funding cuts, and given ongoing fiscal constraints of the federal government it is likely that future opportunities will be extremely limited. Passive acoustic recorders have provided the greatest number of detections of SRKWs over the past six years. At the seven moorings that are currently deployed from Cape Flattery, Washington to Pt. Reyes, California we have detected SRKWs approximately 180 times. Despite this relatively large sample size there are numerous multi-week gaps in the locations of the whales, such that a high degree of uncertainty continues to exist with respect to their winter range. It also important to note that the latter method, while providing the most data to date, does not provide real time sightings. Therefore, the information gained is limited to location data after the recorder has been recovered such that there is no ability to respond to detections in order to conduct predation event collection, etc. It is important to note that all of these methods are limited by inclement weather which biases the data obtained and limits their effectiveness. These techniques are also location specific: where we locate the recorders and where the ship goes is based on past sightings, and visuals sightings are restricted to nearshore or areas of regular whale watch activity. The sighting data for SRKWs obtained to date are clustered based on effort more than anything else. These biases can be directly addressed by satellite tag data.
While it has been suggested that aerial surveys are a useful non-invasive technique, the NWFSC has not used this method due to the small benefit for the high costs incurred. Aerial surveys are expensive relative to the amount of information they return, i.e., although they have the advantage of covering a lot of area relatively quickly, even if a killer whale sighting is obtained we still may not be able to ascertain even the ecotype, much less photos suitable for individual ID, because of the need to maintain altitude for safety reasons. In addition, the prevalent inclement weather during winter severely restricts aerial operations, much more so than an ocean-class survey vessel. Aerial surveys have been attempted to assess the winter distribution of gray whales off the Washington coast in the 1990s and this approach was determined to be very limited.
In addition, although the NWFSC has approached the Navy about obtaining killer whale detections on its hydrophone systems to monitor SRKW movements, the Navy’s response is that there is “no Navy environmental hydrophone network along the US West Coast”. The Navy also noted that “Any other “Navy” system would be more operational and classified, in addition to not being used for environmental analysis.”
What is the risk of satellite tagging to the whales?
We believe the risks to the whale’s health, reproductive success, and survivorship to be extremely low, and are essentially insignificant. NMFS conducted an Environmental Assessment on the effects of issuing the scientific research permit and concluded that there would not be a significant impact on endangered species. The Section 7 consultation on the research permit concluded that the effects of the proposed action would not likely jeopardize the continued existence of this ESA-listed species and would not likely destroy or adversely modify designated critical habitat. These assessments are based on extensive testing and evaluation of the tagging system - having been deployed on over 250 cetaceans of 16 different species during the past six years. To date, there is no indication of serious injury or mortality subsequent to tag implantation. The extent of impacts to the whales post tag-loss is typically a small raised area at the site of the dart penetrations on the dorsal fin and sometimes some depigmentation of the epidermis, all of which is within the range of naturally occurring marks.
For example, both cookie cutter shark bites and bites by conspecifics and other types of wounds frequently occur on the various killer whale eco-types in the North Pacific. SRKWs, due to limitations in their range do not incur cookie cutter shark bites. Over a quarter of SRKWs have definitive nicks on the trailing edge of their dorsal fin and although their source origin is unknown it is likely given the numerous rake marks on their bodies that these are bites from conspecifics. We do not consider any of these previously noted wound types as being substantial because they do not affect survival or reproduction.
Concerns have been raised about how tagging might exacerbate the potential for SRKW to be further immuno-compromised due to their relatively high contaminant burdens. The extent to which SRKW are immune-compromised due to toxin loads is unknown. It has been documented that they are above levels that harbor seals have been shown to be immune-compromised. However, even if individuals were immune-compromised the wound caused by dart penetration is minor, and based on veterinarian assessment, to date; these would be unlikely to be of significant risk to the animal’s health.
We have worked to address the potential for tagging to exacerbate decreased immune-competence due to high contaminant levels with tags deployed on other species. For example, the contaminant levels in Hawaiian Insular false killer whales are between those of SRKWs and Alaska resident killer whales. This similarity to SRKW contaminant loads is due to life history characteristics and feeding at a similar trophic level. In addition, transient killer whales have far higher contaminant burdens than SRKWs. For neither false killer whales nor transient killer whales have there been what would be interpreted as infected tissue during or following dart out-migration. However, based on consultation with veterinarians, even if a localized infection were to occur, it is extremely unlikely that this infection would become systemic.
We recognize that the risk to whale health is not zero, but rather it is extremely small, such that we do not believe that tagging any individuals will directly or indirectly result in serious injury, decreased reproductive output (no reproductive age SRKW females will be tagged) or mortality. We have examined the resighting rates of tagged and non-tagged pilot whales and false killer whales, (which were tagged opportunistically, i.e., there were not tagged based sex or age) and we did not find a reduction of resighting rates. NMFS has issued several permits for dart and other forms of implantable tagging of multiple endangered species with no mortalities or serious injuries documented. In fact, NMFS has issued permits for tagging other small, endangered cetacean populations; i.e., North pacific right whales. However, it is important to note that many of the SRKWs we are proposing to tag are likely near the end of their natural life span, such that it is anticipated that some tagged animals may disappear from the population post-tagging. Consequently, it is important to note that should tagged-animals disappear during, or shortly after post-tagging, this occurrence should not be interpreted as a direct consequence of tagging.
How are you minimizing potential impacts to the whales and population?
Following a very small number of tag attachment failures that were detected in 2010, the tags and darts were redesigned to reduce the likelihood of breakage on impact. The redesigned tags have been thoroughly tested and all have worked well. been available for about six months. None of the several redesigned tags that have been deployed have failed.
We are authorized to tag a very limited number of SRKWs - a maximum of two per pod per year, for a total of six per year. However, we expect the reality of the logistics associated with deploying this many tags to substantially constrain these efforts, and result in fewer deployments than what are authorized. Because we are only interested in winter movements our only opportunities will be when the whales enter Puget Sound in the late winter or we encounter them on the outer coast. These very limited opportunities will be further constrained by workable conditions (day length and sea state) for small boat operations.
In addition, close proximity access to the small number of whales that are designated eligible for tagging will further limit opportunities. Consequently, based on previous encounter experience, we consider it likely that we will only tag a couple of whales/year.
Which whales will be tagged?
Part of the mitigation is to err on the side of caution by selecting animals that do not contribute directly to the reproductive potential of the population (i.e., reproductive females) regarding the animals that will be considered for tagging. Consequently, only adult, whales; post-reproductive females and adult males will be tagged.
What tags will be used?
The remotely deployed satellite-linked tags were originally developed by Russ Andrews (of the University of Alaska Fairbanks and the Alaska SeaLife Center) to examine movements of killer whales in Alaska and the Antarctic.
Other researchers are also using these tags in Alaska and California to study movements of both fish-eating and mammal-eating killer whales as well as to study the study movements of cetaceans in Hawaiian waters (see more information at http://www.cascadiaresearch.org/hawaii/satellite.htm) and off the coasts of California, Washington and Alaska.
The tags are comprised of a transmitter (which is about the size of a standard 9- volt battery) that will uplink to System Argos receivers mounted on weather satellites (see more info below) and two short (about 6 cm) retention darts.
How are the tags deployed and how do the whales react?
The tags are deployed with a Pneumatic dart projector from about 4-12 meters. The darts penetrate the fin tissue and the retention petals secure the transmitter to the fin.
We typically only see a “flinch” by the whale and a more rapid than normal dive. In some cases there was no observed response. In most cases we are able to re-approach the whale for photographs within a few minutes of tagging.
How do the tags work?
Satellite-linked tags transmit a signal to a satellite, and position data is then relayed to the researcher. The Argos system functions very differently than the Global Positioning System (GPS) most people are familiar with. The transmitter on the whale emits a signal when the whale is at the surface and during the specific hours of the day when the transmitter is programmed to be on (to conserve battery life). The signal the transmitter emits is received by System Argos receivers on NOAA’s polar orbiting weather satellites (the transmitter produces a quarter watt signal that has to be detected by a satellite 800 miles above). Weather satellites orbit overhead about every 90 minutes, are overhead for only about 8-14 minutes and are generally most directly overhead during the morning hours to give weather forecasters a first look at cloud cover and/or environmental data the satellites collect. Assuming the satellite is overhead when the tag is turned on and the whale is at the surface, several signals are sent by the transmitter to the satellite receiver. When tag transmissions are received, these signals are then sent to a ground station which sends the entire transmitter ID and frequency information to Argos headquarters in France for processing. Getting an estimated location requires the emission and receipt of a series of signals from a very stable frequency of the transmitter, and using a principle known as Doppler shift (this is what occurs when you hear a train horn sounding lower at the instant it passes by) a series of algorithms are applied to the signal data to estimate the transmitter signal’s location. Each location we receive has a location quality rating which estimates the amount of error associated with it. Argos has seven location quality ratings, four of which have no error estimate associated with it - in other words the location may be correct or may be off by dozens of miles. For the three ratings that have error estimates assigned to them the actual locations are generally accurate within a couple of miles. Determination of the final set of locations requires the use of a filtering program to select those points that have the highest probably of being correct, based in part on the speed between consecutive locations. The result is a detailed and relatively accurate track of the whale’s movements for the time the tag was on during the day.
We receive the location information once a day in the form of an e-mail from ARGOS, and can also access it on-line, although there is a delay (anywhere from 20 minutes to several hours) before the information is available on-line. We will periodically post maps of the whale’s movements.
When would tagging occur?
Tagging will only be conducted in the early winter to early spring - late December through April, in order to determine winter movements. Tagging would occur when the whales come into Puget Sound or during coastal surveys. This tagging will be timed to maximize chances for follow up/sample collection on NOAA ocean-class vessel surveys or other survey efforts. If tags are deployed during ocean-class vessel surveys we will attempt to track the whales for the duration of the cruise with the goal of collecting a variety of data including predation event samples and feces to determine winter prey selection and stress hormones. To the extent feasible, but recognizing the substantial constraints associated with lack of daylight and persistently inclement weather, coastal small boat operations will be undertaken on an opportunistic basis.
How will you assess if there are any effects to the whale?
During all encounters of populations of whales that may have been tagged, most if not all of the individuals in the group are photographed. In many cases, previously tagged animals are identified during the encounter. We do look for both physical (e.g., is the animal emaciated or how has the tagging site healed?) and behavioral (e.g., does the animal surface/dive/swim normally, is it associating with conspecifics?) cues to assess potential effects.
Over the past six years a total of over 250 tags have been deployed on 16 species. We have conducted both dedicated and opportunistic resighting efforts. Despite the challenges associated with resighting animals that can range widely, a substantial number of the tagged animals have been resighted both during the time the tag was attached as well as post-tag loss. In no instance have we observed any anomalous behaviors or change in overall health status of the animals.
In fact we have noted that one of the transient killer whales that was tagged gave birth post-tagging, as has a Cuvier’s beaked whale.
How much data do you expect to obtain?
The median duration of signal contact for tagged killer whales is approximately 31 days with some deployments exceeding 3 months. We typically receive several reliable locations/day. Consequently, for each deployment we expect to acquire several hundred new locations.
What organizations will be involved in the tagging project?
The project will be led by the NWFSC with logistical support from Cascadia Research Collective due to their extensive of experience in the deployment of satellite tags. We will provide location data from the satellite tags in a timely manner to the Center for Whale Research and DFO Canada and other researchers so that they have the opportunity to locate the whales to obtain resighting data that will be used to assess the whale’s condition and the condition of the fin tissue at the tag attachment site.
Links to other killer whale tagging projects
Southwest Fisheries Science Center (Antarctic killer whales)
NWFSC/Cascadia Research Collective transient killer whale tagging
Video clip of killer whale tagging operations as part of an ongoing study by Southwest Fisheries Science Center to understand killer whale predation on gray whales.
Web site owner: Northwest Fisheries Science Center