The owner of a 7-year-old pug that died during a Hawaii Superferry voyage is warning other pet owners of the danger of heat exhaustion.

Jarod Buna, 31, of Manoa, also would like to see the interisland ferry implement procedures to ensure animals are placed in well-ventilated areas during the 3 1/2-hour trip between Honolulu and Maui.

Hawaii Superferry said yesterday it had been notified of only one other incident in which a dog died while in transit. In that case, the owner of the elderly animal did not file an incident report "as he felt that the dog was already very old and might not be strong enough to make the trip," according to a company statement.

Superferry also expressed its "deepest sympathy" to Buna "for the loss of his family pet."

"We will review our procedures to remind our customers of actions to keep their pet safe and comfortable," the statement said.

The company does not keep records of how many animals have been transported on the ferry, but the Department of Agriculture reported that at least 80 dogs sailed from Honolulu to Maui last month and 65 on the return trip.

When vehicles carrying animals check in at the Honolulu or Kahului ports, a magnetic cone is placed on the roof so ferry employees can easily identify pet-carrying vehicles, the company said. "Throughout the voyage, staff members regularly check on these animals to ensure that they're traveling well and that vehicle windows are properly ventilated. The ship master also keeps the vehicle deck between 50 and 85 degrees Fahrenheit when live animals are present."

Buna's blonde female pug, Mattie, died Friday while traveling to Maui on the ferry. On two prior occasions, the attorney and his fiancee, Brandy McDougall, had flown to Maui with their dogs, but Buna said the Superferry seemed an attractive option because they could load their pets and pet supplies in their car and drive on to the vessel.

Mattie and another pug, Teddy, were in separate kennels in Buna's Honda sports utility vehicle. He said they had taken care to walk and water the dogs before boarding the ferry in Honolulu around 3:30 p.m.

"We're very protective of them," he said.

Buna was directed to park toward the enclosed front of the parking deck. He said the car windows were left partially rolled down.

The ferry also allows dogs to travel freely inside a vehicle at the owner's discretion, as long as the windows allow adequate ventilation while preventing the animal from escaping.

Vehicle owners are not allowed on the vehicle deck during the voyage.

Upon arrival at Kahului Harbor around 7 p.m., McDougall was first to reach their car to check on the dogs.

"She noticed that Mattie was just lying on her side and Teddy was not moving very fast. She put Mattie on the floor of the boat and started CPR. She was screaming for help but no one from the ferry was around," Buna said.

The couple's first concern was finding a veterinarian to help Teddy, so they drove out of the ferry terminal without notifying the company that Mattie had died during transit, Buna said.

Veterinarian Mimmi Walther at the Central Maui Animal Clinic in Kahului, where Mattie was examined, said the dog likely died of overheating. Two hours after it died, the dog's temperature was nearly 108 degrees, according to a statement from Walther. A pug's normal temperature is 101 to 102 degrees.

The couple took the ferry back to O'ahu on Sunday, but Teddy flew back in the cabin of a Hawaiian Airlines jet with McDougall's sister.

Pugs and other dogs with short, pushed-in faces are susceptible to brachycephalic airway obstruction syndrome. These dogs, which include Boston terriers, Pekingese, shar-peis, boxers, bulldogs and shih tzus, can have trouble breathing, especially in heat and humidity.

Some airlines will not allow snub-nosed breeds to be transported when the air temperature is above 70 degrees.

Veterinarian Eric Ako of The Pet Doctor in Kahala said he wouldn't recommend traveling with brachycephalic dogs during the hot summer months.

Ako recalled a recent incident in which a couple rushed to his clinic with one dead pug and others in crisis after the dogs suffered heat exhaustion during a sightseeing drive around O'ahu in an air-conditioned van.

"You need to be wise about heat and what kind of breed you have," he said. "Certain breeds are very heat-sensitive and they don't do well in any kind of heat. This sounds like a most unfortunate accident."

Buna said he was aware that pugs are sensitive to heat before going on the Superferry, but said the company should offer information on the travel risks for pets and provide a well-ventilated area for vehicles with animals.