Vaquitas with calves seen in September 2018 field effort

A field effort to obtain photographs and biopsies of vaquitas was carried out from the Museo de Ballena’s 130ft vessel, the Narval, plus several small boats (3 RHIBs and a panga) between 22 and 28 September 2018. Cell culture was supplied by the San Diego Zoo and small field coolers specially set up for field use in hot temperatures were supplied by Southwest Fisheries Science Center (SWFSC). The purpose of the biopsy effort was to obtain live tissue from a male vaquita to complement the two female cell cultures already maintained in the frozen zoo. SWFSC also loaned much of the equipment needed for the visual searching (25x Big-eye binoculars with stands, handheld binoculars, computers and VHF radios). The visual team tracked vaquitas using a computer program specially modified for use with vaquitas (WinCruz Vaquita) that had been developed for VaquitaCPR (see our news article summarising that effort). Acoustic equipment (CPODs) was supplied by WWF and SEMARNAT.

Sightings were made on the two good-weather days, with the most exciting result obtained on 26 September. Sighting #003 was of what was assumed to be a mother-calf pair surfacing within a body length of one another over 30 times. The mother was photographically matched to the likely mother of the calf that was captured and released in 2017 during the VaquitaCPR operation. This pair observed in September 2018 was tracked for an hour.

Screen image of sighting #003. The Narval is in the center with its path indicated by yellow circles. Each concentric white circle is 1 nautical mile. The linked red squares show the path of the mother/calf pair showing the meandering and unpredictable pattern that made positioning of the small A boats difficult.

The recently acquired acoustic data indicate that the remaining vaquitas are staying together and within a single small area. This gives hope that it will be possible to photo-identify remaining individuals (and obtain a biopsy) as well as to guard them effectively during the upcoming totoaba season from December through May. Many thanks to Diego Ruiz Sabio and Museo de la Ballena for sponsoring the field effort, and to SEMARNAT-CONANP for the research permits.

A New York Times Article on the 17th Oct 2018: Scientists Catch Rare Glimpses of the Endangered Vaquita summarised the field effort.

See below photos and video of the sightings.

Photo/Video credit: Lorenzo Rojas-Bracho