The number of humpback whales seen in coastal waters fell once again during this weekend’s Sanctuary Ocean Count, continuing a trend this season and beyond.

Only 34 humpback whales were spotted Saturday during the peak 15-minute period of the third and final monthly count on Oahu, Kauai and Hawaii island. That compares with 85 whale sightings tallied during the peak of last year’s event in late March.

“We’re not surprised by it,” said Mark Lammers, research coordinator with the Hawaiian Islands Humpback Whale National Marine Sanctuary. “It’s consistent with what we’re observing on the water, which is that there’s relatively few whales compared to previous years.”

The news comes on the heels of the lackluster results of the Great Whale Count conducted on Maui by the Pacific Whale Foundation. A total of 529 humpback whales were sighted Feb. 24, which was a significant drop from the 984 seen the year prior and 1,488 the year before that.

The numbers prompted Pacific Whale Foundation researchers last month to suggest that the peak of the whale season is shifting.

“Something is changing,” said Stephanie Stack, senior research biologist with the foundation.

But Lammers cautioned that the citizen- science whale counts, while valuable, should not be solely relied upon to draw conclusions.

“It’s important not to react to one number,” he said.

Sanctuary officials said more than 440 volunteers collected data from 43 sites on the three isles Saturday. While weather conditions were outstanding on Hawaii island, they were less than perfect on Oahu and Kauai, where some viewing sites were shut down due to rain, thunder and lightning.

Earlier in the year, sanctuary volunteers reported 135 whale sightings during the peak of February’s count from 44 locations on Oahu, Kauai and Hawaii island, while 172 whales were seen from 46 sites during the peak of the January count.

The year before that, sanctuary officials said, the three ocean counts in 2016 recorded some of the lowest numbers in five years.

For 18 years the sanctuary has held the the Ocean Count during the the peak of the humpback whale season to promote public awareness about the species, the sanctuary and shore-based whale-watching opportunities.

Participants count humpback whale sightings and document surface behaviors during a survey that offers a snapshot of humpback whale activity from the shoreline.

More than 10,000 humpbacks are estimated to migrate from Alaska to Hawaii for breeding and birthing primarily between December and April, although some whales come as early as October and leave as late as June.