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NOAA technical memorandum NMFS-NE ; 245

Scientists from the United States and Canada collaborated on aerial surveys for North Atlantic right whales (Eubalaena glacialis) along the Scotian Shelf and in the Gulf of St. Lawrence during the summer of 2015. Contributors included researchers from the National Oceanic and Atmospheric Administration (NOAA), Fisheries and Oceans Canada (DFO), Dalhousie University, the Canadian Whale Institute, and the New England Aquarium. The surveys were directed over bathymetric features potentially attractive to right whales and areas being monitored by passive acoustic gliders. The survey platform was a de Havilland Twin Otter (DHC-6). Two observers scanned the ocean surface for right whales while flying at 230m and 100 knots. Sighting locations of all whales, dolphins, basking sharks, and sea turtles were recorded along with sighting conditions including Beaufort sea state, visibility, and glare.

Under the 1994 amendments of the Marine Mammal Protection Act (MMPA), the National Marine Fisheries Service (NMFS) and the United States Fish and Wildlife Service (USFWS) were required to generate stock assessment reports (SARs) for all marine mammal stocks in waters within the U.S. Exclusive Economic Zone (EEZ). The first reports for the Atlantic (includes the Gulf of Mexico) were published in July 1995 (Blaylock et al. 1995). The MMPA requires NMFS and USFWS to review these reports annually for strategic stocks of marine mammals and at least every 3 years for stocks determined to be non-strategic. Included in this report as appendices are: 1) a summary of serious injury/mortality estimates of marine mammals in observed U.S. fisheries (Appendix I), 2) a summary of NMFS records of large whale human-caused serious injury and mortality (Appendix II), 3) detailed fisheries information (Appendix III), 4) summary tables of abundance estimates generated over recent years and the surveys from which they are derived (Appendix IV), a summary of observed fisheries bycatch (Appendix V), and a list of reports not updated in the current year (Appendix VI). Table 1 contains a summary, by species, of the information included in the stock assessments, and also indicates those that have been revised since the 2014 publication. Most of the changes incorporate new information into sections on population size and/or mortality estimates. A total of 43 of the Atlantic and Gulf of Mexico stock assessment reports were revised for 2015. The revised SARs include 27 strategic and 16 non-strategic stocks. This report was prepared by staff of the Northeast Fisheries Science Center (NEFSC) and Southeast Fisheries Science Center (SEFSC). NMFS staff presented the reports at the February 2014 meeting of the Atlantic Scientific Review Group (ASRG), and subsequent revisions were based on their contributions and constructive criticism. This is a working document and individual stock assessment reports will be updated as new information becomes available and as changes to marine mammal stocks and fisheries occur. The authors solicit any new information or comments which would improve future stock assessment reports.

The North Atlantic Right Whale Sighting Survey (NARWSS) is a NOAA Fisheries program, which locates and records the seasonal distribution of North Atlantic right whales (Eubalaena glacialis) off the northeastern coast of the United States. NARWSS flights conducted in 2014 followed systematic tracklines with randomized starting locations within 12 primary survey blocks: Cashes Ledge, coastal Maine, Franklin Basin, Georges Basin, Georges Shoal, Great South Channel, Howell Swell, Jeffreys Ledge, Jordan Basin, Lindenkohl Basin, Rhode Island Sound, and Stellwagen Bank (Figure 1). During 2014, NARWSS flew 245 hours over 55 surveys (Table 1), including a directed flight over right whales in Cape Cod Bay and 2 sawtooth flights in Atlantis Canyon. NARWSS detected 278 right whales (including possible duplicate sightings of the same individuals), with 244 right whales sighted within survey blocks and 34 right whales sighted during transit to or from survey areas. Table 1 summarizes survey effort and right whale sightings by month. Figure 2(ad) displays the locations of right whales and survey effort by season. In 2014, NARWSS did not conduct aerial surveys from February - March or August - October. In July, surveys were conducted in Canadian waters and are detailed in a separate report (Cole and Henry 2015). A comparison of NARWSS flights, flight hours, and right whale sightings from 2002 through 2014 is included (Figure 3, Table 2). Although sightings in 2014 rebounded compared to the low rates in 2013, the number of right whales seen per flight hour was still lower than observed between 2007 and 2011. Internal and external requests for NARWSS survey data are summarized in Table 3.

Under the 1994 amendments of the Marine Mammal Protection Act (MMPA), the National Marine Fisheries Service (NMFS) and the United States Fish and Wildlife Service (USFWS) were required to generate stock assessment reports (SARs) for all marine mammal stocks in waters within the U.S. Exclusive Economic Zone (EEZ). The first reports for the Atlantic (includes the Gulf of Mexico) were published in July 1995 (Blaylock et al. 1995). The MMPA requires NMFS and USFWS to review these reports annually for strategic stocks of marine mammals and at least every 3 years for stocks determined to be non-strategic. Included in this report as appendices are: 1) a summary of serious injury/mortality estimates of marine mammals in observed U.S. fisheries (Appendix I), 2) a summary of NMFS records of large whale human-caused serious injury and mortality (Appendix II), 3) detailed fisheries information (Appendix III), 4) summary tables of abundance estimates generated over recent years and the surveys from which they are derived (Appendix IV), and a list of reports not updated in the current year (Appendix V). Table 1 contains a summary, by species, of the information included in the stock assessments, and also indicates those that have been revised since the 2013 publication. Most of the changes incorporate new information into sections on population size and/or mortality estimates. A total of 30 of the Atlantic and Gulf of Mexico stock assessment reports were revised for 2014. The revised SARs include 12 strategic and 18 non-strategic stocks.

Opportunistic reports were used to measure levels of human - caused serious injury and mortality to baleen whale stocks along the United States east coast and Atlantic Canadian Provinces for 2009 through 2013. Whale injury and mortality events were evaluated using criteria for injury severity and for assigning injuries and mortalities to natural or human causes. The average annual human-caused serious injury and mortality rate during the period was 4.55 for North Atlantic right whales, 9.0 for Gulf of Maine humpback whales, 3.55 for Western North Atlantic fin whales, 0.4 for Nova Scotian sei whales, 7.7 for Canadian East Coast minke whales, 0.2 for Northern Gulf of Mexico Bryde's whales, and 0 for Western North Atlantic blue whales. The number of serious injuries and mortalities not reported is unknown, and actual levels may be much higher.

National Oceanic and Atmospheric Administration (NOAA) funding and Fisheries and Oceans Canada (DFO) collaboration provided the opportunity for the Northeast Fisheries Science Center (NEFSC) right whale aerial survey team to follow right whales into Canadian waters after completing surveys in the waters off the Northeast United States. We completed eight flights in several areas of the Scotian Shelf during July 18- 30, 2014 , under SARA Section 73 Permit # 330996. From a Twin Otter flying at 230m and 100 knots, two observers scanned the ocean surface for megafauna for a total of 22 hours and 16 minutes of visual effort. Eleven right whales were sighted and photographed for individual identification. One was previously injured and is on a list of whales whose health status is being monitored (Right Whale Catalog #1203). Right whale sighting details are provided in Table 1. Table 2 provides the numbers of other megafauna species recorded on each flight. Table 3 provides flight log notes. Table 4 lists the project's participants. Figures 1 - 5 show completed track lines and locations of sightings. The images taken of right whales have been submitted to the North Atlantic Right Whale Catalog at the New England Aquarium in Boston, MA , for individual identification. Copies of the survey data and right whale images are available from Tim Cole.

The MMPA requires NMFS and USFWS to review these reports annually for strategic stocks of marine mammals and at least every 3 years for stocks determined to be non - strategic. Included in this report as appendices are : 1) a summary of serious injury/mortality estimates of marine mammals in observed U.S. fisheries (Appendix I), 2) a summary of NMFS records of large whale/human interactions examined for this assessment (Appendix II), 3) detailed fisheries information (Appendix III), and 4) summary tables of abundance estimates generated over recent years and the surveys from which they are derived (Appendix IV).

During 2013 , NARWSS flew 185 hours over 48 surveys, including directed flights over right whales reported near Atlantis Canyon, Cultivator Shoal, Great South Channel, and Nantucket Sound. NARWSS detected 45 right whales (including possible duplicate sightings of the same individual), with 30 right whales sighted within survey blocks and 15 right whales sighted during transit to or from survey areas. Table 1 summarizes survey effort and right whale sightings by month. Figures 3a-d display the locations of right whales and survey effort by season. In 2013, NARWSS did not conduct aerial surveys from February - April or August - October. Figure 2 and Table 2 provide a comparison of NARWSS flights, flight hours, and right whale sightings from 2002 through 2013. In 2013, right whale sightings were an order of magnitude lower than in previous years (0.17 right whales per hour of survey effort in 2013 compared to the previous average of 1.47 right whales per hour of survey effort). Table 4 summarizes internal and external requests for NARWSS survey data.

The Northeast Fisheries Science Center (NEFSC) developed criteria to evaluate reports of human-caused mortality to baleen whales. The criteria minimize the likelihood of incorrectly assigning whale mortalities t o human causes and provide a minimum count of human-caused events. This report describes determinations made for reports received from 2008 - 2012 involving North Atlantic right (Eubalaena glacialis), humpback (Megaptera novaeangliae), fin (Balaenoptera physalus), sei (B. borealis), blue (B. musculus), minke (B. acutorostrata), and Bryde's (B. edeni) whales observed in United States waters in the Gulf of Mexico, along the US eastern seaboard and in the Atlantic Canadian provinces. We confirmed a total of 3 00 mortalities: 60 (20%) caused by human interaction, 14 (5%) because of natural causes, and 236 (75%) which lacked sufficient evidence to determine cause of death. Of the human-caused mortalities, 32 were due to entanglement and 28 were vessel strike. These mortality numbers are minimum counts because of a low probability of detecting events and inadequate documentation to determine cause of death for the majority of events that are detected. Despite the minimum values, the mean annual confirmed human-caused mortality rate exceeds the Potential Biological Removal (PBR) value for 4 of the 7 stocks examined, including North Atlantic right, humpback, sei, and Bryde's whales. The true level of anthropogenic mortality to these stocks is greater than these minimum values, but the amount greater is unknown.