The stranding of a basking shark at Marine Parade beach, Napier is relatively unusual, but what makes it more unusual is that it was of a relatively small juvenile says Department of Conservation’s marine technical advisor Clinton Duffy.
Duffy was responding to questions posed by BayBuzz around whether it was unusual to have a dusky dolphin washing up on Mangakuri Beach about 30kms east of Waipukurau, a pod of orcas at Napier Port, and the shark at Marine Parade beach, all in the space of a week.
Duffy said while the shark and dolphin were ‘unusual’ for Hawke’s Bay, the pod of orcas was normal around this time of the year.
“It is not unusual to see dolphins and orca in Hawke’s Bay. While sightings of dusky dolphins are relatively uncommon in the Bay, they have been tracked by air up the Wairarapa coast from Kaikoura in the past,” Duffy said.
“We are not anticipating shark sightings to be more common this year in comparison to previous years. Shark sightings, of multiple species, usually peak over spring and summer as more people head to the coast, and several coastal shark species move inshore to pup and feed on abundant inshore fish.
“During this period, calm conditions and cleaner water also makes sharks easier to spot.”
Duffy said the basking shark stranding was unusual.
“This species was very common around southern New Zealand prior before 2000. Schools of 10s to 100s of basking sharks between 6-9 m in length were regularly seen in Cook Strait, off Kaikoura, and around Bank’s Peninsula up until the mid-late 1990s,” he said.
“There were also regular sightings off New Plymouth, Otago Peninsula and around Stewart Island.
“While there continue to be irregular catches of basking sharks in deepwater trawl fisheries, sightings of the species in coastal waters have almost completely stopped – up until November 29 the last confirmed sighting of a basking shark in coastal waters was in Tory Channel in 2012.”
Basking sharks are the second largest fish in the world, with some reports estimating their maximum size at more than 12 m long.
He said “almost nothing” was known of basking shark reproduction and growth and maturity, and observations of juveniles are rare globally.
“Orca range all around the NZ coastline, dusky dolphins are most common around South Island, as are basking sharks.”
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