Hawaii’s third largest island, Oahu, is known for many things — from its beautiful beaches and waters to its interesting plants and flowers, the island has plenty to offer. And now, Oahu has given scientists and society when researchers found previously undetected colonies of at-risk seabird species.
Both Newell’s Shearwaters and Hawaiian Petrels, seabirds typically only found in Hawaii, have been a focus of conservation efforts from some time now. These birds, like many other species, are seeing their habitats destroyed, being hunted by invasive predators and being exposed to a variety of other threats. Between 1993 and 2013 alone, the populations of shearwaters decreased by 94% and petrels by 78%.
Fortunately, a recent study in The Candor: Ornithological Applications shows that despite the fact that these bird species were believed to have left Oahu in the late 1700s, both species are present on the island. The birds do currently breed on other some Hawaiian islands, including Maui and Kauai, but it was quite a surprise to find them on Oahu.
Researchers from Pacific Rim Conservation identified potentially suitable breeding habitats for the birds and tried to detect their presence using automated acoustic recording units. Between 2016 and 2017 the recording units were placed at 16 different sites across the island in hopes of hearing the birds’ calls.
Lindsay Young, researcher leader, explained, “We were doing a statewide survey for these species for the U.S. Fish and Wildlife Service as part of recovery action planning, but Oahu was not initially included as one of the sites to survey, since evidence suggested they weren’t there. Since we’re Oahu-based, we thought we would at least put a few recording units out to see if there was anything.”
And it’s a good thing the researchers expanded their study area because they ended up detecting shearwaters at two of the sites and petrels at another.
There are plenty of environmental efforts in place to help provide good habitats for all animals, like using primary and secondary waste treatments to remove about 85% of pollutants from wastewater before it’s returned to local waterways. Unfortunately, many populations of various species continue to decline, which is why these findings are such big news.
The birds found on Oahu could be either young birds that migrated from other islands or they could be the last survivors of the island’s breeding populations. Either way, the researchers are hopeful that they’ll be able to use social attraction to bring the birds from various islands together. This way, the bird population would be more abundant and could potentially bring the species’ declining numbers back up.