A federal scientist says a recent surge of baby bottlenosed dolphin deaths has a precedent four years ago in Texas.

In March 2007, 68 dolphins washed up in Galveston and Jefferson counties. National Oceanic and Atmospheric Administration scientist Blair Mase says those included an unusual number of infants.

NOAA spokeswoman Kim Amendola (am-en-DOH-luh) says that this year in Mississippi, Alabama, the Florida panhandle and Louisiana, 48 dolphins were stranded and 29 of them were calves. The calf deaths were concentrated in Mississipi and Alabama.

Possible causes include cold winter and disease. Scientists also are investigating whether there was a link to the BP oil spill. But they say the only spike in deaths is in one dolphin species.

THIS IS A BREAKING NEWS UPDATE. Check back soon for further information. AP's earlier story is below.

NEW ORLEANS (AP) — A scientist says the deaths of about two dozen baby bottlenose dolphins is unprecedented in 30 years of studying dolphin deaths in the Gulf of Mexico.

Moby Solangi says the Institute of Marine Mammal Studies in Gulfport, Miss., has no record of previous mass deaths in which the majority were infants.

The recent deaths occurred in birthing areas off Mississippi and Alabama. Six bodies intact enough for dissection were a mix of stillborn, premature and full-term calves that died shortly after birth.

Solangi says possible causes include cold winter and disease. He said scientists are investigating whether there was a link to the BP oil spill. But he says only one dolphin species — and no other kind of animal — appears to be dying in unusual numbers.