Another ‘Baby Boom’ Southern Resident Killer Whale has Died

Posted September 27, 2017 at 5:55 am by

J52 show­ing the char­ac­ter­is­tic “peanut head” depres­sion behind the out­line shape of the skull cov­ered by a thin blub­ber lay­er. Note eye in front of eye­patch — Ken Bal­comb photo

Sad news from the Cen­ter for Whale Research…

As of 19 Sep­tem­ber, anoth­er South­ern Res­i­dent Killer Whale, J52 — a two and a half year old male born dur­ing the so-called Baby Boom of 2015/2016 is deceased, pre­sum­ably from mal­nu­tri­tion. His oblig­a­tory nurs­ing end­ed more than a year ago, and his life was depen­dent upon salmon that have become in short sup­ply this summer.

He was last seen alive near the west entrance of the Strait of Juan de Fuca on 15 Sep­tem­ber 2017, and pho­tographs tak­en at the time reveal severe “peanut-head” syn­drome asso­ci­at­ed with impend­ing death. Young J52 was accom­pa­nied by his moth­er (sev­en­teen and a half year old, J36) and an adult male (twen­ty-six year old L85, poten­tial­ly his father) at least five miles away from the oth­er mem­bers of J and L pods that were for­ag­ing with­in a mile or two of the coast­line from Camper Creek to Bonil­la Point west of Port Ren­frew, British Columbia.

The obser­va­tion of this sad event was at sun­set, and the young whale appeared very lethar­gic while bare­ly sur­fac­ing as the two adults were swim­ming around in cir­cles and not feed­ing while atten­tive to the young whale. We esti­mat­ed J52 was with­in hours, if not min­utes, of death at the time, and he was not present dur­ing the J pod for­ay into Puget Sound on 19 Sep­tem­ber, though his moth­er and L85 were. The moth­er did not appear over­ly ema­ci­at­ed on either occa­sion, but she is lean and seems dis­tressed. Yes, these ani­mals do exhib­it emo­tion, and death of an off­spring brings it on. It is wor­thy of note that all of the SRKW observed this sum­mer appear skin­ny and small com­pared to Bigg’s Tran­sient killer whales in the Sal­ish Sea that have abun­dant prey resources (seals and oth­er marine mam­mals). Tim­ing of food avail­abil­i­ty is every­thing, espe­cial­ly in crit­i­cal phas­es of growth or gestation.

With the pass­ing of J52, three of the six whales born in J pod dur­ing the so-called Baby Boom, which began in Decem­ber 2014 with the birth of J50, have now died; and, two moth­ers (J14, J28) and a great-grand­moth­er (J2) in the pod have also died. No south­ern res­i­dent killer whales from any of the pods have been born alive and sur­vived thus far in 2017 – the baby boom is over. This pop­u­la­tion can­not sur­vive with­out food year-round — indi­vid­u­als metab­o­lize their tox­ic blub­ber and body fats when they do not get enough to eat to sus­tain their bod­ies and their babies. Your diet doc­tor can advise you about that. All indi­ca­tions (pop­u­la­tion num­ber, for­ag­ing spread, days of occur­rence in the Sal­ish Sea, body con­di­tion, and live birth rate/neonate sur­vival) are point­ing toward a preda­tor pop­u­la­tion that is prey lim­it­ed and non-viable. We know that the SRKW pop­u­la­tion-sus­tain­ing prey species is Chi­nook salmon, but resource man­agers hope that they find some­thing else to eat for sur­vival, at least beyond their bureau­crat­ic tenure. Our gov­ern­ment sys­tems steeped in short-term com­pet­ing finan­cial motives are pro­cess­ing these whales and the salmon on which they depend to extinc­tion. If some­thing isn’t done to enhance the SRKW prey avail­abil­i­ty almost imme­di­ate­ly (it takes a few years for a Chi­nook salmon to mature and repro­duce, and it takes about twelve years for a female SRKW to mature and repro­duce), extinc­tion of this charis­mat­ic res­i­dent pop­u­la­tion of killer whales is inevitable in the cal­cu­la­ble future. Most PVA’s (pop­u­la­tion via­bil­i­ty analy­ses) show func­tion­al extinc­tion as a result of no viable repro­duc­tion with­in decades to a cen­tu­ry with cur­rent predator/prey tra­jec­to­ries, but it can hap­pen more quick­ly than that.

Facts about SRKW:
South­ern res­i­dent killer whale females become sex­u­al­ly mature short­ly before or dur­ing their ear­ly teens, and they typ­i­cal­ly have their first viable off­spring in their mid-teens fol­low­ing a ges­ta­tion of approx­i­mate­ly 17 months. The new­born off­spring, called calves, are typ­i­cal­ly about 7–8 feet long and weigh about 400 pounds. They depend on mother’s milk for much of their first year and begin eat­ing sol­id food (pieces of salmon pro­vid­ed by moth­er and oth­ers) after six to nine months. Young whales of both sex­es in this pop­u­la­tion remain with their moth­er for their life­time. Mother’s life­time aver­ages slight­ly more than fifty years, but she typ­i­cal­ly becomes repro­duc­tive­ly senes­cent in her ear­ly for­ties. On aver­age, she can pro­duce five calves in her life­time, and some females have a post-repro­duc­tive life­time of up to fifty more years dur­ing which time they baby-sit and lead their fam­i­lies to feed­ing areas that they have learned about in their life­time. The males in this pop­u­la­tion begin to mature in their mid-teens but gen­er­al­ly do not father calves until their late teens; and, they are most pro­duc­tive of father­ing by their mid-twen­ties. Old­er males father a dis­pro­por­tion­ate­ly high num­ber of off­spring and mate with a vari­ety of females with­in the SRKW pop­u­la­tion. Some females have calves by a ‘favorite’ mate, and oth­ers spread the gene pool out more. The adults in this pop­u­la­tion grow to about 18–23 feet in length (males larg­er than females), and weigh four to six tons. Eighty per­cent of their known diet con­sists of Chi­nook salmon, a large and nutri­tious migra­to­ry fish that used to be in great abun­dance, but is cur­rent­ly Endan­gered through­out most of its range. The south­ern res­i­dent killer whales are also Endan­gered, due to dimin­ish­ing food supplies.

For more infor­ma­tion on the South­ern Res­i­dent killer whales, please refer to our web­site www.whaleresearch.com
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Email: info@whaleresearch.com

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Categories: Animals, Wildlife

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