Quantcast
Latest Stories

Mass whale strandings not a family affair—study


WELLINGTON—Whales that beach themselves in large groups are not all members of the same family, a study has found, undermining long-held assumptions about the cause of mass strandings.

An international team of scientists studied 12 mass strandings in Australia and New Zealand to examine the theory that healthy whales beach themselves while trying to help sick or disorientated family members who have run aground.

After examining the DNA of 490 whales they concluded the so-called “caregiving model” did not stand up, as most of the whales were not related.

Further, it found that many stranded calves were discovered with no mother nearby.

The study was led by Marc Oremus of Auckland University in New Zealand, where mass whale strandings are common.

“If kinship-based social dynamics were playing a critical role in these pilot whale strandings, first, we would expect to find that the individuals in a stranding event are, in fact, all related to each other,” he said.

“We would (also) expect that close relatives, especially mothers and calves, would be found in close proximity to each other.”

In the study, the position of each stranded whale was mapped to determine if individuals found near each other were related.

No correlation was found between location and kinship, even with nursing calves and their mothers, who were often widely separated when the group drove itself onto shore.

Co-author Scott Baker from Oregon State University in the United States said the study, published Friday in the Journal of Heredity, suggested the break-up of family groups in deep water might be a reason for mass strandings.

“In the past people tried to explain mass strandings of pilot whales due to environmental causes or something that’s social — like pursuit of prey into shallow unfamiliar territory,” he told Radio New Zealand.

“They might get disoriented, misled about depth and slope. That’s been one of the primary hypotheses.

“The other is the individuals are supporting each other in some way, one may be ill and the others are supporting them and following them into the beach as a last resort.”

With the second reason now in doubt, Baker was asked if the first was the only logical alternative, but said researchers now had another view.

“We actually pose a new hypothesis that there are social forces at work but these may not be specifically kinship driven care behavior as assumed in the past,” he said.

“We think there might be competition between groups or some sort of disruption prior to stranding.”

The study suggested that disruptions prior to stranding could be due to feeding or mating competition, and even aggression among pods.

It speculated that distress calls from whales in trouble could create confusion among others in the vicinity, resulting in the separation of kin before they end up stranding themselves.

The researchers said the study had implications for attempts to refloat whales after they have stranded.

“Often, stranded calves are refloated with the nearest mature females, under the assumption that this is the mother,” said Baker.

“Unfortunately, the nearest female might not be the mother of the calf — our results caution against making rescue decisions based only on this assumption.”


Follow Us

Follow us on Facebook Follow on Twitter Follow on Twitter


Recent Stories:

Complete stories on our Digital Edition newsstand for tablets, netbooks and mobile phones; 14-issue free trial. About to step out? Get breaking alerts on your mobile.phone. Text ON INQ BREAKING to 4467, for Globe, Smart and Sun subscribers in the Philippines.

Tags: Animal Behavior , Animals , stranding , Whales




Copyright © 2014, .
To subscribe to the Philippine Daily Inquirer newspaper in the Philippines, call +63 2 896-6000 for Metro Manila and Metro Cebu or email your subscription request here.
Factual errors? Contact the Philippine Daily Inquirer's day desk. Believe this article violates journalistic ethics? Contact the Inquirer's Reader's Advocate. Or write The Readers' Advocate:
c/o Philippine Daily Inquirer Chino Roces Avenue corner Yague and Mascardo Streets, Makati City, Metro Manila, Philippines Or fax nos. +63 2 8974793 to 94
Advertisement
  1. Estrada: Gigi Reyes won’t testify vs JPE
  2. Cagayan mayor shot dead after flag-raising ceremony
  3. Obama, family cause a small stir at Easter service
  4. Santiago sees Palace hand in Gigi’s return
  5. ‘Malang’ next crocodile attraction after ‘Lolong’
  6. Gigi Reyes’ only option: tell all
  7. Malaysia Airlines jet turns back after tire burst
  8. Ancient enigmatic carvings in danger of disappearing
  9. New plant to boost supply of clean energy
  10. More bodies from ship; transcript reveals wavering
  1. Kim Henares needs a reprimand, says Cayetano
  2. Suspect in Vhong Navarro mauling tries to leave PH
  3. More legal woes for Cedric Lee
  4. Enrile chief aide back in PH ‘to face charges’
  5. ‘No real progress in PH if dynasties not dismantled’
  6. Henares on Pacquiao bashing: I did not start this
  7. ‘Mom, I love you,’ says text from student on sinking ferry
  8. Massive infra spending set
  9. Fr. Suarez says last Mass on Easter before returning donated land to San Miguel
  10. I’ll follow my conscience on Estrada, says JV Ejercito
  1. KL confirms Malaysian Airlines Flight MH370 ended in Indian Ocean
  2. MRT passengers pass the hat for 6-year-old Ashley
  3. Rookie, lady cops lauded for quick response to MOA heist
  4. Malaysia averts another air tragedy; pilot lands troubled plane safely
  5. Revilla says he was joking; Lacson stands by his story
  6. Revilla ‘consulted’ Lacson on how he evaded arrest
  7. Cudia, dismissed for lying, got 99% in conduct
  8. Police rule out foul play in Helena Belmonte’s death as boyfriend is ‘traumatized’
  9. Kim Henares needs a reprimand, says Cayetano
  10. Hammer-wielding robbers cause chaos at Philippines’ Mall of Asia
Advertisement

News

  • Bernice Lee arrested by NBI team
  • Group: Bataan cop killed to stop him from exposing colleagues linked to drug ring
  • Chemical Engineer licensure examination
  • Troubled history fuels Japan-China tension
  • Palace: Our concern is to ensure MRT runs smoothly
  • Sports

  • NLEX fights off Derulo Accelero to remain unbeaten
  • Mayweather diehard Bieber eats pride, poses with Pacquiao for photo op
  • Power Pinays rip Singapore to enter quarters in Asian volley tilt
  • PBA D-League: Waves edge skidding Superchargers
  • Ilad’s last-second basket lifts Gems over Bakers
  • Lifestyle

  • Miss America: Don’t suspend teen over prom invite
  • Transitions and resurrection in the performing arts
  • ‘Archaeology tour’ of Cebu’s heritage of faith
  • Historic Fort Bonifacio tunnel converted into a septic tank
  • ‘Imports’ from London, and play of the year
  • Entertainment

  • Arrest warrants out vs. Deniece Cornejo, Cedric Lee, et al over serious illegal detention
  • Lindsay Lohan says she had a miscarriage
  • Discovery network cancels Everest jump
  • ‘Captain America’ stays strong atop US box office
  • Easter musings
  • Business

  • Century Pacific Food sets IPO price at P13.75 per share
  • Oil prices down in quiet Asian trade
  • Asian shares mixed in holiday-thinned trade
  • BDO seen keen on bidding for Cocobank
  • Bataan freeport investment pledges up 1,302%
  • Technology

  • PH has slowest internet in Southeast Asia
  • Nintendo’s trailblazing Game Boy marks 25th anniversary
  • Nasa’s moon-orbiting robot crashes down
  • Netizens pay respects to Gabriel Garcia Marquez
  • Nokia recalls 30,000 chargers for Lumia 2520 tablet
  • Opinion

  • Gigi’s home
  • Palace stonewalls on MRT inquiry
  • Couple of things too
  • There is plenty of water behind Wawa Dam
  • Triduum thoughts of a young boy
  • Global Nation

  • Balikatan could spoil peace talks, says militant group
  • DFA officers hold workshop on aiding human traffic victims
  • Canada in communication with PH on toxic wastes
  • Filipinos in Middle East urged not to panic amid MERS-CoV scare
  • Obama on mission to quiet Asia skeptics
  • Marketplace
    Advertisement