Dolphin Quest staff and supporters were rocked by the death of one of their charges this weekend.

Riddells, at 33 the Southampton facility's oldest inhabitant, died due to complications relating to her advanced age and pregnancy -- which was only recently discovered.

"We are tremendously saddened by the death of our dolphin, Riddells,'' said Dolphin Quest's director of animal management, Dave Gossman.

"She was a great ambassador for her species and touched many lives, from those of us who cared for her, to the many children and adults in Bermuda and visitors from around the world.

"We are comforted in knowing that she was happy and playful in her environment at the Southampton Princess and lived a full life.'' Dolphin Quest spokeswoman Lynn Hassell said Riddells was much older than the average life expectancy of Bottlenose dolphins which is estimated to be 17 to 19 years old. She added there were no plans to replace Riddells.

The news marred the end of a weekend which started joyfully.

On Saturday The Royal Gazette revealed that Riddells and a second dolphin, Cirrus, 22, were pregnant.

At the time, Dolphin Quest founder Rae Stone warned that Riddells might experience complications due to her age.

Medical and ultra-sound examinations had revealed that Riddells' foetus was slightly underdeveloped and less active than expected, she said.

Yesterday Dr. Stone noted: "Although there is a great deal of excitement about Cirrus' pregnancy, it is important to be realistic about the possibility of future complications or losses.'' Studies of wild dolphins have shown a high mortality rate in the first year of life, with newborn survival estimated at less than 50 percent.