The carcasses of whales tend to show up in Hawaii waters this time of year, and the Department of Land and Natural Resources is asking boaters who spot any in open ocean to make a report before the floating dead animals wash up on shore.

Sperm whales are usually 30 to 60 feet long and their carcasses pose challenges in terms of swimmer safety and damage control, DLNR Director William Aila Jr. said.

"(A carcass) brings large predators close to shore. We’d like fishermen to let us know ahead of time, so we can take the proper steps to secure the animal," Aila said during a news conference Monday at the Kalanimoku Building.

If it washes up on a reef, the carcass is much harder to remove, Aila said. He compared the slippery mass to gelatin.

"By us grabbing that whale before it goes to shore, it solves a safety issue for us, it solves a logistic problem for us and it also allows that whale to be taken offshore so it can go through its natural deterioration process," Aila said.

Coast Guard and National Oceanic and Atmospheric Administration staff can tow the animal as far as 30 miles offshore to provide nutrients for deep-water ecosystems and create a "hot spot" for fishing, Aila said. Carcasses are towed to areas with currents that won’t bring them to shore.

THE last sperm whale carcass that washed ashore in Hawaii was in March at Naalehu on Hawaii island, said NOAA program manager David Schofield.

While carcasses can wash up on shore at any time of year, sperm whale carcasses are most often seen in the summer months, the DLNR said in a news release.

One to four dead sperm whales typically wash up on Hawaii shores annually. While the reason behind the spike between May and August is largely unknown, ocean currents are a factor, Aila said.

The DLNR is asking boaters to report the latitude and longitude of any spotted carcasses on maritime radio channel 16 or to the NOAA marine mammal hot line at 888-256-9840.