Texas Marine Mammal Stranding Network

Dedicated to the conservation of marine mammals through rescue and rehabilitation, research and education.

Pathology Reports

Now you can search TMMSN Pathology reports for specific terms. (e.g. morbillivirus, spinner dolphin, kogia, etc.)

See Pathology Reports for:  Galveston    Corpus Christi    Louisiana    Port Aransas    Port OConnor    Sabine Pass

Introduction by:  D.F. Cowan M.D., Professor of Pathology

We have an ambitious goal, which is to explain the cause of stranding and the cause of death in every animal we examine. Ultimately, we hope that this information will be useful in the rehabilitation of live strandings. Explaining the cause of stranding or death is relatively easy to do for some animals. A boat injury or brain parasitism is pretty straight forward. Others, such as the appearance on the beach of a very young animal with no sign of disease we explain by circumstance; that is, we believe this animal died because of separation from its mother.

This seems reasonable and make biological sense, although from another perspective it is all surmise. We have come to think of solitary stranded adults as sick, and the babies as lost. In support of this kind of interpretation is the relatively good survival rate of live stranded infants, as compared to adults. It is rare to have any history on a stranded animal, which is important in understanding the meaning of our findings. This is why it is so important to examine animals that die after a period of rehabilitation. These are well known because of the constant recorded observations made during life. The longer the rehabilitation period before death, the more is known and the more valuable the animal is, scientifically. Accuracy of diagnosis, the interpretation of the results of laboratory testing and the effect of treatment can be evaluated. Thus, the information learned from the death of an animal that may have become very important to those providing its care is not lost, but put to the service of those animals that come later.

This is a case by case investigation, and useful and instructive as it is, the real value of the necropsies becomes apparent when the records add up to a view of the segment of the population that strands on our beaches. Those of you who have had the opportunity to attend or even assist at an examination will know that we collect weights of all organs from every animal, and collect tissue samples from every organ and every tissue. As a result of this, we have been able to publish the first comprehensive tables of organ weights for the Atlantic bottlenose dolphin. This provides a frame of reference for us and for other researchers. (Turner, et al, 2005)

We have over 90 animals in our records, and so far as we know, this record is unique in the world for depth of detail on a single species. This allows us to compare weights of current animals with the organ weights of the total recorded population, both by age and body length as well as body weight, sex and maturity status. This is an important aid in evaluating whether an organ is abnormally large or small, but it also provides a basis for comparison with Tursiops truncatus collected in other places. It might tell us about adaptation to different environmental stressors, which might have effects on such things as the size of the liver, adrenal glands or thyroid, as well as suggest stock differences. It is a significant contribution to knowledge in its own right. We have been systematically collecting thymus glands and lymph nodes from the various sites around the body, and anal and pharyngeal tonsils from every animal. We have also described a gland inside the larynx that appears to be most analogous to the adenoid.

This collection of tissues has allowed us to develop detailed anatomic descriptions of the lymphoid system of Tursiops truncatus, useful not only as a basic contribution to classical anatomy, but also serves as a reference base for evaluating possible deficiencies in the immune system that could conceivably result from virus infection or some toxin in the environment. Over the years we have described a disease, amyloidosis, not before seen in dolphins. Had we not been doing systematic studies, we would not have seen that our cases occurred in a relatively short time cluster, and had not reappeared for several years, until recently. Our report led to the recognition of amyloidosis in two whales stranding in Japan.

We have also identified a new disease in Tursiops truncatus, angiomatosis, that has been increasing in frequency and severity over the past several years. We have found an incidence and severity of arthritis that has been surprising, especially since it occurs in quite young animals. Some is clearly infective, but most is of the kind most often associated with aging. Again, the persistent and systematic study of individual cases with detailed record keeping allows insights into disease progression not otherwise attainable. So far we have been describing the anatomy and diseases that can be recognized using observation and the microscope.

We have also been collecting bacterial samples for culture, and testing blood for evidence of hepatitis. We have identified over 60 species of bacteria, and found several animals that give a positive test for viral hepatitis. Our testing of tissues for heavy metals has been done and published as a Ph.D. thesis, by Beth Turnbull, DVM. This allows us to correlate organ weights, diseases, metals burden, pattern of infection, season of the year as well as age and sex into a comprehensive description of the stranded population over seven years. Again, I think this study, for comprehensiveness and detail is probably unique in the world. And none of it would have been possible without the dedicated efforts of the Network volunteers.

Pathology Training 101 - Click here for a quick lesson on the terms used in pathology reports.


GA1415 March 13, 2007
GA1415, GA 1415 was a large (269 cm) male bottlenose dolphin, Tursiops truncatus. Not being in our own necropsy lab, we were not able to get a body weight. He was recovered dead, code 2, from Bolivar peninsula, Galveston County, on March 13. We did the necropsy the following day at Moody Gardens, which is kindly allowing us to use their facility for the time being.

GA1383 January 30, 2007
GA 1383, a 229 cm long male bottlenose dolphin, Tursiops truncatus, was recovered dead from Jamaica Beach, Galveston County, on January 30 2007. He had been seen and photographed alive around 8:30 AM. By the time TMMSN recovery team arrived he was dead. He was brought to the facility at Moody Gardens, for necropsy that afternoon.

GA 1027 February 22, 2000
GA 1027, a 277 cm long 211 kg male bottlenose dolphin (Tursiops truncatus) was recovered dead from the Gulf side beach about 1 mile east of San Luis Pass, Galveston Island, Galveston County. The original observer claimed that the animal was alive and moving (1:45 pm) but by the time TMMSN workers arrived, it was dead. Necropsy was begun at 7:00 PM.

GA 1000 September 15, 1999
GA 1000 was a 120 cm long, 56.4 Kg female bottlenose dolphin, (Tursiops truncatus), recovered alive from 0.2 miles west of Bolivar Flats Road, Bolivar Peninsula, Galveston County, September 15, 1999. She was placed in the collecting truck to be brought to the rehabilitation tank, but she died within about 2 hours.

GA 997 May 30, 1999
was a 228 cm long, 78 kg male Pan-tropical Spotted Dolphin (Stenella attenuata) recovered alive from Bryan Beach, Freeport, Brazoria County, Texas on May 30, 1999. While most of the animal seemed intact, there were two very deep and several shallower cuts, gouges and abrasions in the tail stock and the flukes.

GA 947 May 1998
GA 947 was an infant male (Tursiops truncatus) measuring 109 cm long and weighing 16.4 KG. He was recovered dead, Code 2, from 0.2 miles east of Sea Isle light, Galveston, April 20, 1998.

GA 881 February 5, 1998
GA 881 was a large (250 cm) female (Tursiops truncatus) recovered dead, Code 2, from Eleven Mile Road, Galveston, December 13 1997. She weighed 155 Kg, and was determined by Jason Turner to be 27 years old, based on tooth aging.

GA 810 April 21, 1996
This animal (GA 810), a female Stenella attenuata weighing 64.7 Kg and measuring 191 cm long, was recovered alive 3.5 miles west of San Luis Pass, Brazoria county on April 21, 1996. She died in truck on the way to the laboratory at about 2:30 PM.

GA 775, March 18, 1996
GA 775, a 240 cm female (Tursiops truncatus) weighing 153 Kg, was recovered dead from the beach at Galveston State Park, Galveston, Galveston County, at 11:30 pm on March 18, 1996. She was found within 1 mile of the neonate which stranded on March 16, and may have been its mother, as she had delivered recently and was lactating.

GA 740, January 28 1996
GA 740, a 255 cm long 159 kg male (Tursiops truncatus), was recovered dead, Code 2, from the Gulf-side beach 9.4 miles past San Luis Pass bridge (Surfside) on January 28 1996.

GA 710, Nemo January 12, 1996
GA 710, "NEMO", a large male (Tursiops truncatus) who had been retrieved from the beach last October 29, rehabilitated and released January 12 with a radio tracking device. He washed ashore at 8 1/2 mile road, Galveston Island on January 31. Necropsy findings suggested that he was dead or died very soon after washing up.
GA 706, Hope Report 1-October 10, 1995
"Hope," a pan-tropical spotted dolphin (Stenella attenuata), stranded near Freeport in Brazoria County on August 4, 1995. Although she was unresponsive for some time, her initial condition improved gradually over a period of weeks. Through the dedicated efforts of many volunteers, she survived until October 10th, when it was judged necessary to end her struggle. She was never "right", and always displayed some degree of brain impairment. While she was for a time able to swim by herself, she deteriorated, and eventually lay persistently on her right side. She was seen to inhale water several times.

GA 706, Hope Report 2 - October 10, 1995
Our recently stranded pan-tropical spotted dolphin (Stenella attenuata), "Hope", has tested "positive" for morbillivirus infection. This is our first local stranding with this finding (a group of decomposing animals who drifted ashore last year that tested positive for morbillivirus were probably from the Louisiana area), and since there is a great deal of interest in both the animal and the disease, I have been asked to discuss morbillivirus disease, rather than the usual necropsy report.

GA 705 June 7, 1995
GA 705 was a 210 cm male (Tursiops truncatus) weighing 96.8 G that had been recovered alive from the surf at Galveston Island, Wednesday June 7. This was a slender, immature male, estimated to be about 3 years old, possibly an off shore animal, suggested by the contrast markings, and a number of Xenobalaenus attached to the trailing edge of the flukes. He had been extensively bitten by sharks. All wounds, while extensive, were confined to the blubber, except for one which entered the right flipper joint.

GA 699
GA 699 was a 245 cm long, 140.7 kg female (Tursiops truncatus) found alive during the day at Crystal Beach, Bolivar Peninsula, Galveston County. She died shortly before recovery by TMMSN.

GA 668, October 15, 1994
GA 668, a 145 cm female (Tursiops truncatus) weighing 45.9 kg was recovered dead, Code 2, from the surf at 45th St., Galveston, about 3:30 pm October 15, 1994.

GA 664, August 29, 1994
GA 664 was a 255 cm 130.4 kg female (Tursiops truncatus) recovered dead, Code 2 (very fresh), from East Beach (Galveston Condominiums) Galveston August 29, 1994.

GA 535,
GA 535 was a young, 216.5 cm long female (Tursiops truncatus) recovered dead from the Terrebon Beach/Bay Harbor area, near San Luis Pass, Galveston Island.

GA 484, February 1993
GA 484, a 219 cm long female (Tursiops truncatus) was recovered dead, Code 2, from Emerald Beach Island, 9.8 miles E of the ferry landing (8.53 NM east) 29o 26' 8" N, 94o 38' 7" W, in February 1993. She was estimated to be about 6 years old. Externally, she was in very good condition, with only a few small pits in the epidermis. All the joints were normal.


GA 466 June 26, 1992
GA 466 was a 244 cm long female (Tursiops truncatus) identified about 4:30 pm, Friday June 26, 1992 at Surfside Beach.


GA 440 March 1992
GA 440 was a 247 cm, 38 year old male (Tursiops truncatus) recovered from Surfside Beach, Brazoria County, Texas in March 1992. This animal was one of the oldest we have examined, with its age established by counting the growth layers in the teeth. It has obviously lived an eventful life, evidenced by the heart scars and the enlargement of the adrenal glands, the main organ of adaptation.




GA 407
April 16, 1991
GA407 was a 206 cm long female (Tursiops truncatus) recovered alive on April 16, 1991 from the Pirate's Beach area of Galveston Island. She died shortly thereafter.



Corpus Christi

CC233 March 26, 2006
CC 233 was a male melon-headed whale, Peponocephala electra measuring 246 cm long and weighing 185 kg, recovered alive from Marker 3, Padre Island National Seashore, north (Kleberg County, 27 21 670 N, 47 19 320 W, on March 26, 2006. He was found rolling around in the surf. Although outwardly he appeared to be in reasonably good condition, he seemed unstable, and was retained at the Texas State Aquarium for a period of preparation for transport.

CC 186 April 7, 2002
CC 186 was a 145 cm male bottlenose dolphin, Tursiops truncatus, estimated to be about 2 years old. He was found stranded April 7, 2002 near the 33 mile marker, Padre Island National Seashore (Kenedy County) by USGS personnel. It was reported that he had stranded earlier at the 44 mile marker, but had been pushed back into the water by observers. At the time of retrieval, he weighed 65 kg. He had several wounds attributed to a boat propeller, as well as small shark bites. He was taken to the Texas State Aquarium for care and rehabilitation. He was named ‘Corky’.

CC 162 March 4, 1999
CC 162 was a female bottlenose dolphin, (Tursiops truncatus), measuring 195.8 cm long and weighing 162 KG, recovered alive from 9 miles south of Bob Hall Pier, Kleberg County, Texas, on March 4, 1999. She was taken to the Texas State Aquarium for rehabilitation.

CC 159 December 1998
CC 159 was a juvenile male melon-headed whale Pepononcephala electra, (179 cm long) who stranded alive in Kenedy county in the Corpus Christi region on November 11, 1998. He was taken to the Texas State Aquarium in CC for rehabilitation.

CC 127, Mystery, 26 March 1998
CC127, a young Fraser's dolphin (Lagenodelphis hosei) was found in the surf near Corpus Christi on 22 March, rescued and held in the Texas State Aquarium.

Sabine Pass

SP 383 March 09, 2003
SP 383 was a large (253 cm long, 158 kg) female bottlenose dolphin, Tursiops truncatus. She was recovered dead from Taylor’s Bayou, near Port Arthur, Orange County, Texas on March 15, after a period of intermittent observation for several days.

SP 321 December 8, 1998
SP 321, a 249 cm male (Tursiops truncatus) recovered dead from Sea Rim State Park, Jefferson County, Texas, December 8, 1998. This was a large, probably off-shore male, with many signs of a long and active life.

SP 189 August 1993
SP189 was a 233 cm, 151 kg female (Tursiops truncatus) who died entangled in a net about one mile off the west jetty at Sabine Pass, Jefferson County this past August.

SP 153 February 1992
SP 153 was a 237 cm long female bottlenose dolphin, (Tursiops truncatus), weighing 169.0 kg. Her age was determined to be 19 years, based on the number of dentinal growth layer groups.


LA 042, February, 1998
LA 042 was a 259 cm long male (Tursiops truncatus), weighing 217.5 KG. His age has not been determined yet. He was first found alive at about 3:30 PM 02/24/98, 1 mile east of Tides Inn RV park, Holly Beach, Cameron Parish, Louisiana.

Port Aransas

PA 748 October 28, 2006
PA 748 was a large (295 cm long) male bottlenose dolphin, Tursiops truncatus, weighing 229 kg. Age was determined to be more than 25 years, by counting of the tooth growth layers. We believe that the animal was considerably older than that, but complete closure of the dental pulp cavities prevented more layers from forming. He was recovered alive 28 October, near Corpus Christi, but in the PA region. National Marine Fisheries, South East laboratory personnel recognized that this animal was likely to be non-releasable, and endorsed euthanasia, which was done on November 6. He was brought by truck to Galveston, TX for necropsy.

PA 636 September 11, 2002
PA 636 was an adult male dwarf sperm whale, Kogia sima, 233 cm long, weighing 401 pounds, recovered alive from Matagorda Island Gulf beach, Aransas County, 2.1 m north of Cedar Bayou, Sept 11, 2002, by Tony Amos and brought to Galveston for rehabilitation.

PA 582 December 26, 2000
PA 582 was a 55.3 kg, 183.5 cm long female spinner dolphin (Stenella longirostris) recovered dead by Tony Amos, December 26, 2000 on San Jose Island, Aransas County, Texas. It was very fresh, and may have died just before it was found. It was transported to the laboratory in Galveston for necropsy.

PA 572 August 2, 2000
PA 572 was a young male (Tursiops truncatus), estimated by body size (150 cm, 40 kg) and tooth eruption, to be less than a year old. He was found alive, entangled in the line of a crab pot, about 50 yards from shore in water about 4 feet deep, 1/2 mile north of the Texas State Aquarium (TSA), Nueces County, on August 2. He was released without incident by the Corpus Christi Regional Coordinators, but he did not swim off, and evidently could not hold himself upright in the water. For that reason, after a few hours, with the permission of the National Marine Fisheries Service, he was walked ashore and taken to the TSA for rehabilitation. Unfortunately, he died about 12 hours later and was brought to the Galveston Laboratory for examination.

PA 292 April 11, 1992
PA292 was a 271cm male (Tursiops truncatus) that was recovered from the Gulf beach of Mustang Island in Nueces County on April 11, 1992.

PA 229 October 17, 1991
PA 229 was a mature female (Tursiops truncatus), measuring 247 cm long, weighing 148 kg, recovered about 200 yards south of Bob Hall Pier at Padre Bali Park, Nueces County, October 17, 1991.

Port O'Connor

PO 375 December 18, 1996
PO 375 was a 262 cm long female manatee (Tricheus manatus) reported alive on the beach about 3 miles north of Wynn access road, Calhoun County 10:30 AM, December 18. It died within 1 ? hours, and was removed to Aransas Wildlife Refuge, from which it was brought to the Necropsy Laboratory at TAMUG. The gross examination was done by Dr. Worthy and Lance Clark, in my absence.

PO 355, Miracle November 20, 1996
PO 355 was a 289 cm long male false killer whale, Pseudorca crassidens, who was recovered live from the beach 15.6 nautical miles east of Matagorda town, Matagorda County on November 16. He was put in the recovery truck, which became bogged down on the beach with the tide change. He could not be evacuated until the next day when he was airlifted by Coast Guard helicopter to Galveston. He survived from the 17th to the 20th in the rehabilitation tank at the National Marine Fisheries Service compound. During its time in the tank he had to be supported continuously or else he would roll over and sink.



PO 249 September 1992
PO 249 was a 190 cm female (Tursiops truncatus) weighing 61.6 KG recovered dead, Code 2, from Matagorda Bay in September 1992. This is one of the animals captured, examined and tagged in July 1992 as part of the study into the heavy mortality experienced in the Bay in March. This was the smallest of all the animals taken. At the time, she weighed 76 Kg. Like all the animals in that catch, she was deemed to be in very good condition. She was freeze branded 517 on both sides of the body, and a blubber biopsy taken.

Padre Island

PI 152 March 27, 2001
PI 152 was a young female pan-tropical spotted dolphin, Stenella attenuata, who was recovered alive 5 miles north of access #6, South Padre Island, Cameron County, Texas (26o 17.1 N, 97o 11.4 W), at 10:25 AM, March 27. She was 161 cm long and weighed 33 kg. She was transported to UT - Pan AM for rehabilitation. She did not do well, being unable to swim or to maintain upright posture. She died the following day and was transported on ice to Galveston for necropsy.

PI 141 June 13, 2000
PI 141 was a 242 cm long, 139.5 kg male melon-headed whale, Peponocephala electra, who stranded alive 13 miles north of access road #6, Cameron County, Texas, June 13, 2000. He died shortly after discovery. He was frozen and transported to the Galveston laboratory, where he was necropsied on July 17, 2000.

PI 128 November 27, 1998
PI 128 was a 242 cm, 267 kg male bottlenose dolphin, (Tursiops truncatus), recovered from Beach Blvd, Laguna Vista, Cameron County, Texas, November 27, 1998. He was taken to the University of Texas - Pan American for rehabilitation. He was given supportive care, but he died on December 01. Necropsy was
done by Lance Clark.

PI 093, Miss Kitty August 1, 1996
PI 093 was a 250 cm long 129 kg female bottlenose dolphin (Tursiops truncatus) recovered alive from the beach 1/2 mile north of Brazos Santiago Pass, Cameron County Texas, August 1, 1996.