Death of a California Gray Whale
IAAAM 1990
T.A. Gornall, DVM; Robert A. Fouty, MD

Necropsy report including probable cause of death and mechanism of death.

Specimen:

California Gray Whale

Date of discovery:

06/18/84

Location of discovery:

15 miles west of Port Angeles at mouth of the Lyre River, Washington

Date of necropsy:

06/20/84

Location of necropsy:

Graham, Washington

Organization directing investigation:

Marine Animal Resource Center
Director-Tag Gornall, DVM

Chief investigator:

Medical Laboratory Associates
Director -Robert A. Fouty, MD

Pathologist

 

Final diagnosis

1.  Immature California Gray Whale, Male,27 feet in length

2.  Acute hemorrhagic liver necrosis, massive

3.  Pleural effusion, bilateral, 6000 cc., serosanguineous

4.  Microbiology-normal bowel flora but evidence of reduced growth under aerobic and anaerobic (see Microbiology)

5.  Toxicology-concentrations of the following in decreasing order. ( see Toxicology )

6.  Post mortem changes: approximate 10 days

 

Stool

Liver

Fat

Stool and/or liver

Lindane

1100

18

4 PPB

 

Heptachlor

500

190

4 PPB

 

pp-DDE

57

140

24 PPB

 

Dieldrin

50

210

18 PPB

 

Endrin

11

43

15 PPB

Liver

PCB's

170

750

80 PPB

Stool

Heavy Metals

     
 

Barium

40.3

<0.3

PPM

 

Lead

4.8

0.7

PPM

 

Chromium

4.5

<0.3

PPM

 

Arsenic

2.5

0.32

PPM

Description of Necropsy Findings

General

Length:

27 feet long

Greatest girth:

10 feet

Width chest:

4.5 feet

Width abdomen:

4.8 feet

Estimated weight:

7000 pounds

The carcass is that of a well-developed, well-nourished, immature California Gray whale. The skin surface exhibits some superficial cracking and debridement but otherwise there are minimal post mortem changes and there is no evidence of trauma. Barnacle markings are numerous about the dorsum of the head with approximately 75% of the barnacles missing. The eyes are intact and the cornea are cloudy. The baleen structures are intact. They contain sand and fragments of black debris. The mouth shows no evidence of injury or mucosal ulceration or burns.

The external surfaces of the chest, abdomen, flukes, and flippers appear normal. The genitalia are those of a normal, immature Gray whale.

There are no external signs of injury or chronic illness.

Respiratory System

The upper respiratory system and oropharynx show no abnormalities.

The right and left pleural cavities contain a combined volume of 6000 cc.'s of serosanguineous fluid. The pleural surfaces are smooth and glistening and there is no evidence of fibrosis, infection or malignancy. The right and left lungs measure 36 x 12 x 12 inches respectively. The parenchyma is light red, moderately moist and exudes some fluid when squeezed. Aeration is poor. The trachea is lined by an intact pale yellow mucosa with minimal mucus and no evidence of infection or suggestion of pulmonary edema. The bronchi appear similar to the trachea.

Cardiovascular System

The parietal pericardium is normal. The pericardial sac contains a large normal-appearing heart measuring 12 x 9 x 9 inches. The surface is smooth and glistening. The myometrium is soft and pliable. The chambers contain a decreased amount of blood. The leaflets and cusps are normal.

The aorta and pulmonary vessels appear normal. There is no evidence of trauma.

Gastrointestinal Tract

The esophagus appears normal. The mucosa is intact and there is no evidence of ulceration or desquamation of the surface. The submucosal tissues show no evidence of hemorrhagic change.

The gastro-esophageal junction is intact. There are small areas of hemorrhagic change measuring up to 3 cm in diameter and comprising less than 15% of the total area.

The stomach is empty except for a few grains of sand and debris and mucus totaling 100 cc's. The mucosa is intact without evidence of autodigestion or perforation of the wall.

The upper and lower small bowel are moderately distended with gas. The walls appear intact without evidence of infection, perforation, trauma or neoplasia. The lumen is essentially empty except for a total of 300 cc's of mucus mixed with grains of sand, black debris and green material (probably organic). The mucosa is in excellent condition throughout with out evidence of bacterial digestion, hemorrhage, infection or ulceration. However, there is some submucosal gas which creates a nodular-like elevation of small segments of mucosa.

The lower intestine is moderately distended with gas. The wall is intact and appears normal. Except for the terminal 30 inches of bowl, the lumen is empty except for a total of 200 cc's of mucus with debris. The terminal colon measures 30 inches length and 8 inches in diameter and contains about 3000 cc's of black formed stool. The mucosa of the bowel including the terminal segment is intact.

Liver

The liver consists of a necrotic mass of hemorrhagic, dark brown material which is held together by strands of bile ducts, vessels and fibrous tissue. The capsule is difficult to identify and the liver mass disintegrates with the slightest manipulation.

Pancreas

Pancreatic tissue is identified. It is soft, tan and lobulated. There are no gross abnormalities.

Kidneys

The kidneys appear normal. The surfaces are lobulated and soft. The cut surface has a homogeneous color and the texture is friable.

Genitalia

There are no gross lesions.

Endocrine

Post mortem changes obscure details.

Brain

The brain is sampled for toxicology through the foramen magnum.

Microbiology

Specimens of the upper and lower bowel contents contained similar microscopic viable and non-viable material. This material consisted of various microscopic forms of algae and diatoms. The majority of the specimen consisted of amorphous material and anaerobic and aerobic viable and non-viable bacteria. Microscope reviewed various crystal components and no parasites at this time.

The concentration of bacteria on the microscopic stained smears was much higher than the concentration of viable organisms recovered anaerobically and aerobically. A basic investigation is being performed to see if there are any inhibitory components in the bowel to inhibit the flora.

At the present time we have isolated and identified a number of aerobic organisms such as E. coli, Pseudomonas putrefaciens and a streptococcus species. Anaerobically we have isolated various anaerobic bacterial strains of which only Clostridum paraperfringens has been identified, but further basic identification is in process.

All bacteria identified up to this point are consistent with those found in a young sperm whale named Florence in 1979 and except for concentration levels and some unusual forms are similar to those isolated in the human bowel.

Toxicology: Pesticide: (All residues reported at the PPB level)

 

Fat

Lung

Liver

Gut-Lower

Upper

Stomach

Stool

Lindane

4

1

18

11

17

15

1100

Heptachlor

4

5

190

58

95

60

500

Aldrin

2

1

130

45

14

8

6

Chlordane

36

32

3

<40

20

55

<90

pp-DDE

24

12

140

51

29

39

57

pp-DDT

3

4

<13

6

4

<13

<15

Methoxychlor

2

4

<50

<50

5

<20

<23

α-Endosulfan

7

5

73

<11

4

13

<12

Dieldrin

18

13

210

76

52

45

50

Endrin

15

6

43

<5

7

6

<11

PCBs

80

40

750

80

60

60

<170

Metals: (All reported at PPB level)

Ag

0.18

0.10

0.32

0.57

<0.03

0.24

1.15

As

<0.02

0.02

0.32

1.86

0.09

1.53

2.52

Ba

<0.3

<0.3

<0.3

17.8

<0.3

4.8

40.3

Cd

<0.03

<0.03

0.20

0.12

<0.03

0.11

0.23

Cr

<0.3

<0.3

<0.3

2.1

<0.03

1.4

4.5

Hg

<0.01

<0.01

0.11

0.03

0.01

0.0

0.04

Pb

<0.5

<0.5

0.7

<0.5

<0.5

<0.5

4.8

Se

0.12

0.31

0.51

0.96

0.19

0.42

0.83

Additional Findings

The Northwest and Alaska Fisheries Center, Environmental Conservation Division, Seattle also participated in this investigation. Their conclusions address the presence of Aluminum in blood and brain samples. The lowest concentration of Al found in the whale brain precipitate was 2.2 ppm wet weight. In addition, the whole blood of the whale averaged 2.2 ppm. Dementia in humans exposed to Al has been found with concentrations of less that 0.5 ppm in serum. High levels of water soluble Al were also found in the stomach contents.

The California Gray whale is a coastal migrator that moves from the waters of Alaska to those of Baja California. It is believed that the animals only feed in Alaskan waters, but numerous necropsies of Gray whales in Washington waters evidence that they are feeding. Also, unlike any other whale or any mammalian species, the Gray feeds by sifting debris from the ocean floor. This leaves it uniquely vulnerable to pollution in bottom sediments.

Speaker Information
(click the speaker's name to view other papers and abstracts submitted by this speaker)

Tag A. Gornall, DVM


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