November is the traditional start of hoi kohola, the return of humpback whales to Hawaii, when an estimated 8,000 to 12,000 of the protected marine mammals migrate from their Alaska summer feeding grounds to the islands, where they sing, mate and birth and nurse calves in warm, shallow waters until April, when they start back north.
The 2020-21 season kicked off early last month with the first humpback whale sighting, reported Oct. 8 off Maui, according to Stephanie Stack, chief biologist at the Pacific Whale Foundation on Maui.
“I saw a humpback whale over a month ago, the earliest I have seen one myself,” said Ed Lyman, natural resource management specialist with the Hawaiian Islands Humpback Whale National Marine Sanctuary, in an email Friday. He added that the sanctuary has been getting reports of whale sightings “from all the islands.”
Big questions for this season, scientists and conservationists say, are whether total numbers of whales sighted during upcoming annual counts in January, February and March will continue trending upward after having plunged nearly 50% in 2016, and what effects, if any, coronavirus restrictions on tourism may be having on the mysterious leviathans.
“Whale sightings have been very good over the past two years,” Stack said of Pacific Whale Foundation’s annual volunteer counts at 12 shoreline sites from Hookipa to Makena Beach.
Marc Lammers, research coordinator with the humpback whale sanctuary, has been pioneering underwater acoustic studies of whales off Maui using hydrophones. He said the early months of 2020 saw a five-year high in humpback whale populations in the islands after recent years of decline.
Until 2016, humpback whale populations in Hawaii had been steadily growing since 1970, when, after being heavily depleted by commercial whaling, the species was listed as federally endangered and the U.S. banned commercial whaling in 1971.
From 2004 to 2006, Lyman and 400 other researchers conducted a Structure of Population, Level of Abundance, Status of Humpback Whales survey, which found approximately 10,000 humpback whales wintering in Hawaiian waters. The study also found that the population was growing at a rate of 5.5% to 6% yearly. (In the late 1970s, there were only about 895 whales, Lyman reported.)
In 2016, Hawaiian humpback whales were removed from the endangered species list.
But in the 2015-16 season, “people in Hawaii started witnessing a lot fewer whales, and the trend persisted for a number of years,” said Lammers, who started recording progressively lower decibel levels of whale chorusing in January 2016, the same year the Sanctuary Ocean Count — held annually on Oahu, Kauai and Hawaii — and the Pacific Whale Foundation’s Great Whale Count on Maui started finding yearly decreases in whale numbers.
While no definitive answer has been found, “most researchers agree that a likely culprit is food,” according to a report on the National Oceanic and Atmospheric Administration’s National Marine Sanctuaries website. A trifecta of warming events — an El Nino, a warm phase in the Pacific Decadal Oscillation and an extreme marine heatwave known as The Blob — converged in the whales’ North Pacific habitat in 2013 to 2016, disrupting the flow of nutrients krill depend on and sending whales pursuing the small crustaceans to new feeding grounds.
However, the good news is “we can say that (in 2019-20), whale abundance and singing activity was the highest in about five years, indicating that whale numbers in Hawaii have been increasing,” Lammers said in a webinar he presented earlier this month on the sanctuary’s website.
With regard to any effects from the COVID-19 pandemic, Lammers said that by the time shutdowns began in March, the whale season was already on the wane.
“Unfortunately, we could not say very much about how whales responded to the reduced human activity in late March, (as) our acoustic data show that the season was past its peak by that point and that singing levels were decreasing, (which) is consistent with what we would expect for that time of year,” he said in an email Wednesday.
However, he added, with the slow revival of Hawaii tourism as the new humpback whale season gets underway, “commercial activity is expected to still be relatively low compared to normal years, so we hope to have a chance to get out on the water and determine whether whale behavior has shifted in any way.”
Meanwhile, whale-watch cruises are being offered, subject to counties’ COVID restrictions, said AJ McWhorter, communications specialist for the state Department of Land and Natural Resources. He noted the carrying capacity for inspected vessels in Maui County is 50% of the total passenger carrying capacity, including crew.
Lyman, who rescues and tracks entangled whales, said “we actually had no confirmed, actively entangled large whales reported entangled last season — a first for us.”
This could “at least in part have been due to COVID and fewer people on the water,” he said. But fewer “eyes on the water” also could have affected reporting.
Lyman thanked community members for helping with reporting whale sightings and entanglements. “We have found that rapid reporting, along with documentation, is the best way to help the animals and keep people safe,” he said, urging people to call him the NOAA Fisheries Hotline at (888) 256-9840 with reports.
Volunteers can sign up for the 2021 whale counts on the sanctuary and Pacific Whale Foundation websites. The foundation’s website also allows for downloading of a free app to record whale sightings.
A free live webinar on the Hawaiian cultural significance of humpback whales will be presented from 10 to 11 a.m. Monday by Solomon Pili Kaho‘ohalahala, chairman of the Hawaiian Islands Humpback Whale National Marine Sanctuary Advisory Council, on the sanctuary’s website.
—
WHALE WEBINAR
>> What: free webinar on cultural significance of Humpback whales in Hawaii hosted by NOAA
>> When: 10-11 a.m. Monday
>> Presenter: Solomon Pili Kaho‘ohalahala
>> Register: 808ne.ws/whalewebinar
—
WHALE STATS
>> Number of humpback whales present in Hawaiian waters: approximately 8,000-12,000 per year (source: NOAA)
>> Date humpback whales listed as federally endangered: 1970
>> Date U.S. banned commercial whaling: 1971
>> Number of Hawaii whales estimated by SPLASH survey, the most recent scientific count to date, in 2006: 10,000
>> Date of Northeast Pacific marine heatwave: 2014-2016
>> Date Hawaii humpback whales removed from federal endangered species list: Sept. 2016
>> Seasons citizen science half-day whale counts saw average decreases of up to more than 50% from 2015: 2016-2019
>> Summaries of whales sighted in Pacific Whale Foundation’s annual Great Whale Count Maui
2014: 1331
2015 : 1488
2016 : 732
2017: 984
2018: 529
2019: 690
2020: 840 in Jan., 536 in Feb.
>> Summaries of whales counted in Hawai‘i Marine Mammal Consortium’s annual Sanctuary Ocean Count on Oahu, Hawaii Island and Kauai
2010-2015: 477 whales on average
2016-2017: 261 whales on average