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Biological Characteristics
Species |
Chelydra serpentina is 20-47 cm in length, with a massive head and powerful jaws. Males are often larger than females (McVey et al., 1993). In both sexes, the heavily-serrated carapace is tan to dark brown. (Behler and King, 1979). |
Status in Estuaries |
This species can be found in freshwater and brackish areas, and prefers soft mud bottoms and abundant vegetation. A typical clutch is composed of 25-50 eggs, laid in a deep flask-like cavity that can be several hundred meters from the water (Behler and King, 1979; McVey et al., 1993). Females may lay 1 or 2 clutches per season. In winter months, snapping turtles hibernate by burrowing in mud or debris, sometimes in large congregations, for periods of 5-7 months (McVey et al., 1993). The maximum age of a snapping turtle recorded in nature is 24 years (McVey et al., 1993). |
Abundance and Range |
Snapping turtles occur in the U.S. east of the Rockies, ranging from Canada to the Gulf of Mexico (Behler and King, 1979). |
Site Fidelity |
Most turtles stay in one general area from year to year. One study found 91.9% of turtles returning to the same nesting site one year later (McVey et al., 1993). |
Ease of Census |
Difficult |
Feeding Habits |
Generalists. Snapping turtles eat invertebrates, carrion, aquatic plants, fish, birds, and small mammals (Behler and King, 1979). |
Snapping
Turtle Contaminant Exposure Data |
|
I. |
Organochlorine Contaminants |
A. |
Concentrations
in Adults |
1. |
There
were no detectable concentrations of DDE,
dieldrin, or heptachlor
epoxide present in a female snapping turtle, or its eggs,
collected in Iowa in 1974 (Punzo et al., 1979). |
2. |
Organochlorine
content was measured in fat, liver, skeletal muscle and eggs of snapping
turtles captured in 1976-78 from the Hudson River and other middle and
northern New York localities (Stone et al., 1980). In fat tissue, PCBs
averaged 2990 µg/g lipid weight in Hudson R. and 464 µg/g at other
sites. DDE and dieldrin
were detected in the fat tissue of approximately 70% of specimens at
values <81.30 (Hudson R.) and <34.10 µg/g (other sites). Mean PCB
levels were significantly higher in 23 turtles from Hudson R. at 66.05
and 4.24 µg/g wet weight in liver and skeletal muscle, respectively,
than in 8 turtles from other waters at 7.77 and 0.44 µg/g. DDE was detected in 16 of 18 livers tested from Hudson R. and
5 of 7 from elsewhere, with one value of 17.40 µg/g, and all others
<2.11 µg/g. In skeletal muscle, DDE
was detected in 17 of a total of 24 turtles analyzed, with
concentrations <0.74 µg/g. Dieldrin
was found in 11 of a total of 17 turtles analyzed, with all values
<0.99 µg/g. |
3. |
Fat
from snapping turtles collected from the Hudson River was analyzed for PCDF
(Rappe et al., 1981). PCB
in the fat was found at a concentration of 750 µg/g. A total of 18
different PCDF isomers were detected at the following levels: 45 pg/g TCDFs,
820 pg/g PnCDFs, 700 pg/g HxCDFs,
1000 pg/g HpCDFs, and 350
pg/g OCDF. Total PCDF concentration was 3 ng/g. |
4. |
Two
snapping turtles, one from Irondequoit Bay, Lake Ontario (LO), and
another from the upper Hudson River (HR), were collected and analyzed to
determine their suitability as a biological screen for PCBs (Olafsson et al., 1983). Total PCB
levels were 663 µg/g wet weight in the LO turtle and 3608 µg/g in the
HR sample. Fifty-one congeners were measured in the LO turtle and 46 in
the HR turtle. Other pesticides analyzed were DDE,
87 µg/g LO and 14 µg/g HR, and mirex,
28 LO and 1.9 HR. Due to their high tolerance to toxic substances,
snapping turtles were concluded to be an excellent sentinel species. |
5. |
Two
snapping turtles were collected from separate ponds at a hazardous waste
site in Moreau, Saratoga County, New York in the early 1980's (Watson et
al., 1985). Total PCBs in fat ranged from 81-4,530 µg/g wet weight.
Total PCB concentration
in liver and muscle of the latter specimen was 185 and 17 µg/g,
respectively. The former
specimen had 0.053 ng/g 2,3,7,8-TCDF
in its fat. One snapping turtle had 0.830 ng/g combined penta-
and hexachloronapthalene in its liver. |
6. |
Seventeen
snapping turtles were collected from six locations in Minnesota in 1981
for contaminant analysis (Helwig and Hora, 1983). Concentrations of PCB
ranged from <0.2-60.5 µg/g in fat and were <0.1 µg/g in muscle
for all locations. Highest PCB
concentrations were detected at the Mississippi River locations. |
7. |
Snapping
turtles were collected during the summers of 1981 and 1982 from brackish
and fresh waters of the Hackensack Meadowlands in New Jersey, and
relatively uncontaminated freshwater in Maryland, were analyzed for
metal and organochlorine contaminants (Albers et al, 1986). Sample sizes
per sex ranged between 3-8. PCBs
were detected in the visceral fat of all samples, with a significantly
higher mean of 291.13 µg/g of lipid in males from brackish waters in
New Jersey, and means of 23.55-41.20 µg/g in other locations. Combined
levels of PCB from all
locations were significantly higher in males compared to females. Oxychlordane
was detected in 88% of samples, with locality means ranging between
1.30-9.33 µg/g. cis-Nonachlor
and trans-nonachlor,
detected in 59% and 53% of the turtles, respectively, had similar means
ranging from 0.31-4.01 µg/g. DDE
was detected in 63% of turtles, with a mean concentration of 2.03 µg/g
in from freshwater sites in New Jersey, which was significantly higher
than that for males from brackish waters in New Jersey, 0.16 µg/g.
Males from Maryland also had a significantly higher mean (0.39 µg/g)
than females from the same location (0.10 µg/g). All other
organochlorines were detected in 25% or less of samples. Cis-chlordane
was found only in females from brackish waters in New Jersey (0.12 µg/g)
and DDD only in males from
freshwater in New Jersey (0.13 µg/g). trans-Chlordane
was found in both sexes, but only from the Maryland location, with means
<0.08 µg/g. Dieldrin
and heptachlor epoxide were
found only in turtles from freshwater locations at means <0.07
and <0.38 µg/g, respectively. DDT,
endrin, and toxaphene were not detected in any samples. |
8. |
Abdominal
fat and liver tissues were taken from three snapping turtles collected
from the upper St. Lawrence River in 1984-85 for PCDD
and PCDF analysis (Ryan et
al., 1986). Contaminants were identified in the following concentrations
in fat and liver, respectively, (pg/g, wet weight): 6-300 and <74
2,3,7,8-TCDF, 232-470 and
32-107 2,3,7,8-TCDD, <600
and <100 1,2,3,7,8-PnCDF,
95-3020 and 13-480 2,3,4,7,8-PnCDF,
33-104 and 4.6-22 1,2,3,7,8-PnCDD,
<890 and <480 total
HxCDFs, 16-102 and 3-18 total
HxCDDs, <69 and <13 1,2,3,4,6,7,8-HpCDF,
2.3-17 and 3.7-4.5 1,2,3,4,6,7,8-HpCDD,
and 17-36 and <27 1,2,3,4,6,7,8,9-OCDD.
|
9. |
PCB congeners were compared between a
snapping turtle from an environment with "low pollution" in
Chenango County, New York, to one with "high pollution" in
Saratoga County, New York (Bryan et al., 1987b). Total
PCB (µg/g) distribution in
tissues of turtles from the low and high pollution areas was: 4.2 and
1600 fat, 1.6 and 100 testes, 1.0 and 82 brain, 1.0 and 72 liver, 0.64
and 49 heart, 1.2 and 48 kidney, 1.2 and 48 pancreas, and 0.41 and 13
lungs. A total of 31 congeners were measured and each was detected in
both turtles. Congeners detected in the highest amounts were (low and
high pollution, µg/g): 0.151 and 272 2,4,3',4'-tetrachlorobiphenyl;
0.117 and 297 2,3,6,2',3',6'-hexachlorobiphenyl;
0.54 and 166 2,4,2',4',5'-pentachlorobiphenyl;
0.332 and 152 2,3,6,2',3',4',6'-heptachlorobiphenyl;
and 0.159 and 171
3,4,2',3',4'-pentachlorpbiphenyl. |
10. |
A
male snapping turtle was collected from the Upper Hudson River near
Moreau, New York (Olafsson et al., 1987). PCB
congener concentrations were measured in the adipose tissue,
heart, spleen, pancreas, liver, neck muscle, and testes. Concentrations
in adipose tissue were 0.808 µg/g for 2,3'4,4',5-pentachlorobiphenyl,
1.87 µg/g for 2,3',4,4',5,5'-hexachlorobiphenyl,
2.11 µg/g for 2,3,3',4,4',5,5'-heptachlorobiphenyl,
8.53 µg/g for 2,3,3',4,4',5-hexachlorobiphenyl,
and 33.5 µg/g for 2,3,3',4,4'-pentachlorobiphenyl.
In other tissues, concentrations ranged from 0.0228-0.287 µg/g for 2,3,3',4,4',5-hexachlorobiphenyl,
0.195-1.68 µg/g for 2,3,3',4,4'-pentachlorobiphenyl
and were <0.1 µg/g for 2,3',4,4',5-pentachlorobiphenyl,
2,3',4,4',5,5'-hexachlorobiphenyl,
and 2,3,3',4,4',5,5'-heptachlorobiphenyl. |
11. |
Four
snapping turtles collected from the Tinicum National Environmental
Center in Pennsylvania contained total
PCB concentrations ranging from 11.6-27.3 µg/g in fat
(Schwartz et al., 1987). |
12. |
Organochlorines
were measured in 78 adult snapping turtles collected in 1988-89 from 16
sites in southern Ontario (Hebert et al., 1993). The range of mean
contaminant levels in muscle for all sites were as follows (ng/g wet
weight): 0.00-655.28 total PCB,
0.00-164.60 total DDT,
0.00-3.95 mirex, and
0.00-1.26 OCS. Significant
intersite differences were found for all four substances. A highly
significant relationship was found between contaminants in adult female
turtles and their eggs. |
13. |
Gravid
snapping turtles were collected in New York state (n=6) from 5 different
sites (Pagano et al., 1999). All
amounts are in µg/g. Annandale,
NY, Hudson (sample 1) contained 22.4 PCB,
0.13 DDE, 0.06 mirex,
and 0.05 HCB in liver; 19.3
PCB, 0.29 DDE, 0.04 mirex,
and 0.01 HCB in adipose. Annandale,
NY, Hudson sample 2 contained: liver tissue 68.5 PCB, 0.07 DDE,
0.13 mirex, and 0.02 HCB;
adipose tissue 45.8 PCB,
0.06 DDE, 0.05 mirex,
and 0.01 HCB. Massena,
NY Massena sample contained: liver tissue 695.9 PCB, DDE ND,
8.41 mirex, 0.08 HCB;
adipose tissue 894.8 PCB, DDE
ND, 9.98 mirex, 0.05 HCB. Rochester,
NY, Sodus Bay sample: liver tissue 2.2 PCB,
0.66 DDE, 0.04 mirex,
and 0.02 HCB; adipose
tissue 2.0 PCB, 0.71 DDE, 0.02 mirex,
0.01 HCB. Oswego,
NY, Rice Creek sample: liver tissue 3.8 PCB,
0.93 DDE, 0.17 mirex,
and 0.01 HCB; adipose
tissue 4.7 PCB, 1.10 DDE, 0.15 mirex,
and 0.01 HCB. Oswego,
NY, Industrial sample: liver tissue 140.8 PCB,
DDE ND, 0.42 mirex,
and 0.01 HCB; adipose
tissue 215.3 PCB, DDE
ND, 0.74 mirex, 0.01 HCB. |
14. | Blood was collected from adult snapping turtles in June 2001 and 2002 from 2 sites in Areas of Concern in the Lake Erie basin and 1 reference sites outside of the basin for contaminant analysis (de Solla and Fernie 2004). Contaminants were analyzed per clutch and detected at the following levels (ng/g wet weight): 15.2-96.3 total PCBs, 0.58-4.63 DDE, 0.18-6.65 mirex, 0.13-0.72 HCB, nd-1.12 trans-nonachlor and nd-0.45 cis-nonachlor. |
B. |
Concentrations
in Eggs |
1. |
Organochlorine
content was measured in 6 snapping turtle eggs collected from the Hudson
River in 1976-77, and in the liver and skeletal muscle of adult turtles
also captured from the area (Stone et al., 1980). PCB was present in all of the eggs at a mean of 28.9 µg/g
wet weight. DDE was
detected in all 4 eggs tested at values <0.56 µg/g and dieldrin in all 6 eggs analyzed at levels <0.055 µg/g. |
2. |
A
study on the disposition of toxic PCB
congeners in snapping turtle eggs concluded that 2,3,3',4,4'-pentachlorobiphenyl and 2,3,3',4,4',5-hexachlorobiphenyl
made up more than 99% of the total toxicity in the egg, and that over
95% of the total toxicity resided in the yolk (Bryan et al., 1987a). |
3. |
Snapping
turtle eggs were collected in 1981 and 1984 from a total of 49 clutches
from 9 locations within the Great Lakes-St. Lawrence River basin and one
reference site (Algonquin Provincial Park in Ontario) for contaminant
analysis (Struger et al., 1993). Contaminants were analyzed per clutch
and detected at the following levels (µg/g wet weight, % clutches
detected): 0.0057-4.758 total PCBs
(100%), <0.430 DDE
(98%), 0.220 mirex (84%), <0.130
HCB (46%), <0.100
dieldrin (86%), <0.110
oxychlordane (88%), <0.060
cis-chlordane
(72%), <0.030 trans-nonachlor
(68%), <0.010 heptachlor
epoxide (72%), and <0.040 ß-HCH
(34%). Pentachlorobenzene, 1234-TeCB,
and 1235/1245-TeCB were not detected in any sample. Both high
variation among clutches from the same locality and high variation for
all organochlorines between sites were exhibited. Eggs from Hamilton
Harbour, Port Franks, Bay of Quinte/Murray Canal, and Lake St. Clair
tended to be the most contaminated. Eggs from Hamilton Harbour analyzed
for PCDDs and PCDF contained the following concentrations: 67 pg/g 2,3,7,8-TCDD,
6 pg/g 1,2,3,7,8-PnCDD, 4
pg/g 1,2,3,6,7,8-HxCDD, 1
pg/g 1,2,3,7,8,9-HxCDD, 2
pg/g 1,2,3,4,6,7,8-HpCDD,
and 14 pg/g 2,3,4,7,8-PnCDF.
OCDD, 2,3,7,8-TCDF,
1,2,3,4,7,8/1,2,3,4,6,7-HxCDF,
and 1,2,3,6,7,8-HxCDF were
not detected. |
4. |
In
1981, 1984, 1988, 1989, and either 1990 or 1991, snapping turtle eggs
were collected from nests in five locations in the Great Lakes basin and
from Algonquin Provincial Park (APP) in northcentral Ontario (Bishop et
al., 1996). The following organochlorines were detected (range of yearly
means in µg/g wet weight): 0.32-3.38 APP, 5.27-54.36 other sites, total
PCBs; 0.04-0.49 APP, 0.66-10.65 other sites,
DDE; 0.003-0.02 APP, 0.03-0.35 other sites HCB;
0.01-0.07 APP, 0.05-0.94 other sites dieldrin;
0.003-0.07 APP, and 0.03-2.12 other sites mirex.
Significant differences between sites occurred for each chemical in
various years, though Cootes Paradise/Hamilton Harbour and Lynde Creek
eggs tended to be the most contaminated. Contaminants were determined
for 6 PCB congeners, 8 PCDDs,
and 14 PCDFs. Lynde Creek contained the highest occurrence of these
contaminants with detection all PCB
and PCDD compounds and
11/14 PCDFs. APP was the
least contaminated site containing all PCB
congeners, 1 PCDD, and no PCDFs. |
5. |
Organochlorine
accumulation and intra-clutch variation was studied in snapping turtles
collected from 7 nests in 1986 and 1987 from Cootes Paradise in western
Lake Ontario (Bishop et al., 1995). In comparing the first five eggs
laid, the last five eggs, and a "composite" sample of eggs
laid after the first five and before the last five, the first five
tended to have the highest mean concentrations of chlorinated
hydrocarbons on a wet weight basis and on a lipid weight basis. The last
five eggs tended to have the lowest values, and composite eggs were
generally intermediate. Concentrations for the first five, the
composite, and last five, respectively were as follows (ng/g wet
weight): 43.9, 16.6, 20.9 HCB;
109.2, 92.0, 38.9 cis-chlordane;
298.3, 138.3, 92.1 trans-nonachlor;
487.0, 70.4, 153.7 DDE; and
2099.2, 1716.9, 1653.9 sum PCBs.
Contaminants were quantified in eggs detected at oviposition, at
"stage" 20, 22, and 24 of development, on the day of hatch,
and 18 days posthatch. The percent contaminant transferred from egg at
oviposition into embryo tissues increased for all chemicals until day of
hatch, then decreased at 18 days posthatch. Percentages decreased from
day of hatch to 18 days posthatch by the following amounts: 55.2% to
51.9% HCB; 74.1% to 45.7% cis-chlordane;
90.5% to 52.2% trans-nonachlor;
71.9% to 45.3% DDE; and
88.3% to 62.2% sum PCBs. |
6. |
Snapping
turtle eggs collected immediately after oviposition from Algonquin
Provincial Park (APP) and 4 locations in the Great Lakes between 1986
and 1989 were analyzed for hatching success, incidence of deformities,
and contaminant concentrations (Bishop et al., 1991). A total of 129
clutches were sampled for organochlorine analysis. For 1986-87, APP
contaminant levels were significantly lower than all other sites with
means of 1.3 ng/g wet weight HCB,
76 ng/g total PCBs, and no
detection of cis-chlordane
or trans-nonachlor.
Cootes Paradise and Lynde Creek were significantly higher than all other
sites with means up to 17 ng/g HCB,
112 ng/g cis-chlordane,
136 ng/g trans-nonachlor,
and 2708 ng/g total PCBs.
In 1988-89, Cootes Paradise was significantly higher than all locations
for all contaminants and APP had the lowest values of all but heptachlor
epoxide. Mean values were as follows (ng/g): 0.7-25 HCB,
2.4-112 cis-chlordane,
1.6-249 trans-nonachlor,
8.0-877 DDE, 0.5-143 mirex,
0.6-20 dieldrin, 0.2-5.6 heptachlor
epoxide, and 25-3322 total PCBs.
Of 10 PCDD congeners and 9 PCDFs
analyzed, none were detected in APP, and 17 were detected in Lynde
Creek, the most of any site. |
7. |
Snapping
turtle eggs collected immediately after oviposition from 15 nests in
Hamilton Harbour, Lake Ontario had the following mean organochlorine
levels (µg/g lipid weight): 5.9 DDE,
1.4 mirex, 0.49 dieldrin, 0.02 PCB #52,
1.7 PCB #105, 7.3 PCB
#118, 9.3 PCB #138, 9.3 PCB #153,
6.4 PCB #180, 0.61 PCB
#194, and 54.3 total PCB
(Bishop et al., 1994). No significant correlation was found for body
size and any of the contaminants measured in the eggs. |
8. |
Snapping
turtle eggs were collected from 39 clutches in 10 locations on the St.
Lawrence River and its tributaries in Canada in 1989 and 1990 (Bonin et
al., 1995). Five eggs from each clutch were pooled and analyzed for
organochlorines and mercury, and pools from similar localities were
averaged. The following contaminants were detected in all samples
(ranges of locality means in ng/g wet weight): 106-5094 PCB;
0.4-17.2 HCB; 7.0-372.7 DDE;
0.4-133.5 mirex; 2.8-101.5 oxychlordane;
2.4-128.6 trans-nonachlor;
1.1-85.7 cis-nonachlor;
0.4-10 heptachlor epoxide;
and 2.5-44.6 dieldrin. Cis-chlordane
was found in 92% of samples with means of 0.1-62.4 ng/g and p-mirex
in 82 % with means of 0.1-49.5 ng/g. DDD,
detected in 67% had means ranging from 0.2-16.4 ng/g. Trans-chlordane,
ß-HCH, OCS,
and DDT, detected in 85,
62, 56, and 41% of samples respectively, had mean levels 5.6 ng/g. 1245-TeCB,
1234-TeCB, and pentachlorobenzene,
and
|
9. |
From
1989-1991, snapping turtle eggs were collected from seven study
locations in the Great Lakes basin and St. Lawrence River, and Algonquin
Provincial Park (reference site) in north-central Ontario (Bishop et
al., 1998). Mean total PCB
concentrations were 0.241-3.95 µg/g wet weight at the study sites and
0.018 µg/g at the reference site. Non-ortho
PCB congeners measured were 37
(2.8-27.2 pg/g at study sites, 3.8 pg/g at the reference site), 81
(32.4-960.8 pg/g study, 12.0 pg/g reference), 77 (14.0-256.6 pg/g study, 6.2 pg/g reference), 126
(201.1-2972.2 pg/g study, 51.7 pg/g reference), 169
(11.6-70.1 pg/g study, 2.9 pg/g reference), and 189
(4.2-58.9 pg/g study, 1.1 pg/g reference). When measuring PCDDs
and PCDFs, only one congener was detected at the reference site
(0.9 pg/g 1,2,3,4,6,7,8,9-OCDD).
Other congeners were infrequently detected, with detection of each
congener ranging from all to none of the seven of the study sites.
Maximum mean concentrations (pg/g) were 27.4 2,3,7,8-TCDD,
36.4 1,2,3,7,8-PnCDD, 2.6 1,2,3,4,7,8-HxCDD,
27.0 1,2,3,6,7,8-HxCDD, 2.8
1,2,3,7,8,9-HxCDD, 4.9 1,2,3,4,6,7,9-HpCDD,
10 1,2,3,4,6,7,8-HpCDD, 21 1,2,3,4,6,7,8,9-OCDD,
30.6 1,2,4,7,8-PnCDF, 24.1 2,3,4,7,8-PnCDF,
7.9 2,3,4,6,7-PnCDF, 2.7 1,2,3,6,7,8-HxCDF,
6.2 1,2,4,6,8,9-HxCDF, 1.2 1,2,3,4,7,8-HxCDF,
3.2 1,2,3,6,7,8-HxCDF, 1.8 1,2,3,7,8,9-HpCDF,
0.3 2,3,4,6,7,8-HpCDF, 1.4 1,2,3,4,6,7,8-HpCDF,
0.2 1,2,3,4,6,8,9-HpCDF,
0.8 1,2,3,4,7,8,9-HpCDF,
and 1.6 1,2,3,4,6,7,8,9-OCDF.
Pesticides detected in at least one study site at concentrations <1
µg/g were DDE, DDD,
DDT, 1,2,4,5-chlorobenzene, 1,2,3,4-chlorobenzene,
pentachlorobenzene, photomirex,
mirex,
|
10. |
In
1995, blood samples were collected from adult snapping turtles from four
sites in Southern Ontario (de Solla et al., 1998). Mean total
PCB in blood plasma from males ranged from 0.018 to 0.415 µg/g
wet weight among sites. Mean concentrations of all other organochlorine
contaminants analyzed were <0.025 µg/g. PCB
congeners 37, 81,
77, 169,
and 189 were detected at
colony means ranging from ND to 4.77 pg/g in female turtles, and PCB-126
occurred at means up to 57.68 pg/g. Octachlorodibenzodioxin
reached a maximum mean of 4.59 pg/g in females, while concentrations of
other PCDD and PCDF
congeners were generally <1 pg/g. |
11. |
Gravid
snapping turtles were collected in New York state (n=6) from 5 different
sites (Pagano et al., 1999). All
amounts of contaminants in eggs are in µg/g.
Annandale,
NY, Hudson sample 1: 7.2 PCB,
0.014 DDE, 0.03 mirex,
and 0.01 HCB. Annandale,
NY, Hudson sample 2: 22.3 PCB,
0.06 DDE, 0.02 mirex,
and 0.01 HCB. Massena,
NY Massena sample: 310.1 PCB, DDE
ND, 2.84 mirex, and 0.05 HCB.
Rochester,
NY, Sodus Bay sample: 1.1 PCB,
0.23 DDE, 0.02 mirex,
0.01 HCB. Oswego,
NY, Rice Creek sample: 1.5 PCB,
0.28 DDE, 0.04 mirex,
and 0.01 HCB. Oswego,
NY, Industrial sample: 79.8
PCB, DDE
ND, 0.19 mirex, and 0.01 HCB.
|
12. |
In
June of 1998, 5 eggs were collected from each of 8 clutches in Akwesasne,
Ontario, Canada (de Solla et al., 2001).
Mean
(and SD for Snye) concentrations in snapping turtle eggs at the Raquette
(N=1), Turtle Creek (N=1), St. Regis (N=1), and Snye (N=5) sites were,
respectively: 2, 117, 1, and 0.8 (1.10) ng/g wet weight hexachlorobenzene;
1, 7, ND, and ND ng/g octachlorostyrene;
3, 38, trace, and 1.00 (1.00) ng/g heptachlor
epoxide; ND, 29, 3, and 5.20 (3.90) ng/g oxychlordane;
trace, 27, trace, and ND ng/g cis-chlordane;
16, 176, 4, and 4.20 (4.09) ng/g trans-nonachlor; 29, 852, 11, and 9.80
(7.40) ng/g DDE; 5, 280, 4,
and 3.20 (2.59) ng/g dieldrin;
trace, 2, ND, and ND ng/g DDD;
trace, trace, ND, and trace or ND ng/g DDT;
8, 85, 2, and 2.00 (2.12) ng/g cis-nonachlor; 27, 213, 3, and 6.20 (6.50)
ng/g photomirex; 59, 438,
5, and 12.40 (13.214) ng/g mirex;
5960, 737,683, 6785, and 2378.2 (2116.29) ng/g total
PCB; and 8918, 265,438, 2603, and 2721 (2935.35) ng/g arochlor
1254:1260 (1:1). Turtle Creek had the highest concentrations,
especially that of PCBs. Pooled
snapping turtle eggs had the following concentrations of organochlorines
(in ng/kg): 1064.62 PCB-37,
4564.81 PCB-77, 37418.0 PCB-81,
15042.1 PCB-126, 90.58 PCB-169, 69.43 PCB-189,
6.66 2378-TCDD, 1.06 123678-HCDD,
1.93 12346789-OD, 2.64 2378-TCDF,
1.71 12378-PCDF, 60.48 23478-PCDF,
7.09 123478-PCDF, 3.34 123678-PCDF,
and 0.89 1234678-PCDF. 12378-TCDD and 1234678-HCDD
were not detected. TCDD
equivalents of total PCBs (in ng/kg) for snapping
turtle eggs calculated from Kennedy et al., 1996, Ahlborg et al., 1994,
Van den Berg et al., 1998 were, respectively: 6.07, 0.32, and 0.29 for
Raquette; 736.4, 13.2, and 12.97 for Turtle Creek; 6.72, 0.12, and 0.12
for St. Regis; and 2.56, 0.11, and 0.1 for Snye Marsh. Turtle Creek
values were higher than the other sites. TCDD
equivalents (ng/kg) for pooled snapping turtle eggs
calculated from Van den Berg et al., 1998, were: 0.46 PCB-77,
3.47 PCB-81, 1504.21 PCB-126,
0.91 PCB-169, 1547.46 total non-ortho
PCBs, 6.66 2378-TCDD,
0.11 123678-HCDD, 0.00019 12346789-OD,
0.26 2378-TCDF, 0.086 12378-PCDF,
30.24 23478-PCDF, 0.71 123478-PCDF,
0.33 123678-PCDF, 0.0089 1234678-PCDF,
and 38.41 total PCDD/PCDF. TCDD
equivalents (in ng/kg) for pooled snapping turtle eggs
calculated from Kennedy et al., 1996, were: 0.43 PCB-37,
136.94 PCB-77, 6944.59 PCB-81,
4512.64 PCB-126, 1.81 PCB-169, 11595.4 total non-ortho
PCBs, 6.66 2378-TCDD,
2.9 2378-TCDF, and 9.56 total
PCDD/PCDF. TCDD
equivalents (ng/kg) for pooled snapping turtle eggs
calculated from Ahlborg et al., 1994, were: 2.28 PCB-77,
1504.21 PCB-126, 0.91 PCB-169, 0.069 PCB-189,
and 1547.46 total non-ortho
PCBs. TCDD
equivalents (ng/kg) for pooled snapping turtle eggs
calculated from Safe, 1994, were: 45.65 PCB-77,
1504.21 PCB-126, 4.53 PCB-169, 1554.39 total non-ortho
PCBs, 6.66 2378-TCDD,
0.11 123678-HCDD, 0.0019 12346789-OD,
0.26 2378-TCDF, 0.086 12378-PCDF,
30.24 23478-PCDF, 0.71 123478-PCDF,
0.33 123678-PCDF, 0.0089 1234678-PCDF,
and 38.41 total PCDD/PCDF. TCDD
equivalents (ng/kg) for pooled snapping turtle eggs
calculated from Zabel et al., 1995, were: 0.73 PCB-77,
19.44 PCB-81, 75.21 PCB-126, 0.0037 PCB-169,
95.39 total non-ortho PCBs, 6.66 2378-TCDD, 0.025 123678-HCDD,
0.074 2378-TCDF, 0.058 12378-PCDF,
21.71 23478-PCDF, 1.99 123478-PCDF,
and 30.52 total PCDD/PCDF. |
13. |
Snapping
turtle eggs were collected from 3 sites in Ontario, Canada, for
artificial incubation in June 1998 (de Solla et al., 2002). The three
sites were Hamilton Harbor; number of clutches=14 (heavily contaminanted),
Akwesasne Mohawk Territory; n=3 (moderately contaminated) and Algonquin
Provincial Park; n=14 (reference site). Mean concentrations in ng/g wet
weight. Hamilton
- HCB 2.79, OCS 1.93, Heptachlor
epoxide 3.50, Oxychlordane
31.71, cis-Chlordane
4.29, cis-Nonachlor
33.36, trans-Nonachlor
57.57, DDE 135.14, DDD
2.29, Dieldrin 8.21, Photomirex
19.79, Mirex 42.21, total
chlorinated hydrocarbon 343.79, sum
PCB 2,956.28. Akwesasne
- HCB 1.00, OCS
ND, Heptachlor epoxide
0.67, Oxychlordane 4.33, cis-Chlordane
ND, cis-Nonachlor
2.33, trans-Nonachlor
4.33, DDE 10.00, DDD
ND, Dieldrin
3.00, Photomirex 6.00, Mirex
13.00, total chlorinated hydrocarbon 44.67, sum
PCB 3,377.00. Algonquin
- HCB ND, OCS
ND, Heptachlor epoxide ND, Oxychlordane
0.67, cis-Chlordane
ND, cis-Nonachlor
ND, trans-Nonachlor
ND, DDE 1.67, DDD
ND, Dieldrin ND,
Photomirex ND, Mirex
ND, total chlorinated hydrocarbon 2.33, sum
PCB 20.33. |
14. | Snapping turtle eggs were collected in 1999 and 2000 from Lake Sasajewun, Coote’s Paradise, Walpole Island, and 6 sites in the St. Lawrence River Area (Ashpole et al. 2004). Five eggs from each clutch were collected and pooled for chemical analysis. Contaminants were analyzed per clutch and detected at the following levels (ng/g wet weight): 32-61,000 total PCBs, 6.4-69 DDE, 0.0024-0.028 total dioxins, 0.0012-0.058 total furans, nd-75 mirex and 0.39-14 dieldrin. Hg ranged from 50-720 ng/g dw. |
15. | Snapping turtle eggs were collected in June 2001 and 2002 from 5 sites in 3 Areas of Concern in the Lake Erie basin and two reference sites outside of the basin for contaminant analysis (de Solla and Fernie 2004). Contaminants were analyzed per clutch and detected at the following levels (ng/g wet weight): 15.7-928.6 total PCBs, 1.33-57.9 DDE, 0.18-6.65 mirex, 0.16-2.42 HCB, 0.11-5.86 dieldrin, 1.22-24.4 sumchlordane, 0.06-1.95 heptachlor epoxide, and nd-1.31 octachlorostyrene. Eggs were pooled from 4 sites to determine TEQs. PCB TEQs ranged from 1.83-40.56 pg/g ww. PCDD/F’s TEQs ranged from 1.28-11.22 pg/g ww. |
II. |
Cholinesterase-Inhibiting Pesticides |
|
No
direct exposure data available |
III. |
Trace Elements, Metals, and Metalloids |
1. |
Concentrations
of Cd in the liver and
skeletal muscle of 6 snapping turtles captured in 1976-77 from the
Hudson River ranged from <0.06-26.20 µg/g wet weight and <0.06-
1.41 µg/g, respectively (Stone et al., 1980). |
2. |
Seventeen
snapping turtles were collected from six locations in Minnesota in 1981
for contaminant analysis (Helwig and Hora, 1983). Concentrations of Hg
ranged from 0.05-0.30 µg/g in meat and were 0.04 µg/g in fat.
Concentrations of Cd were
measured in meat only and were 0.025 µg/g for all locations. |
3. |
Snapping
turtles collected during the summers of 1981 and 1982 from brackish and
fresh waters of the Hackensack Meadowlands in New Jersey and relatively
uncontaminated freshwater sites in Maryland were analyzed for metal and
organochlorine contaminants (Albers et al, 1986). Sample sizes per sex
ranged between 3-8. Chromium,
Cu, Hg,
and Zn were detected in
both the liver and kidney of all samples. Mean liver concentrations of Cr
were significantly lower in New Jersey in males from brackish sites
(0.36 µg/g wet weight) than other groups (0.60-1.97 µg/g). In the
kidney, turtles from the two brackish sites showed significantly higher
mean Cr concentrations
(2.97 and 2.70 µg/g) than freshwater locations (<1.26 µg/g).
Mean Cu concentration in
liver was significantly higher in samples from brackish sites (9.72 and
5.17 µg/g) than from freshwater sites (<2.08 µg/g); however,
Cu values in kidney of
males from both brackish and freshwater sites in New Jersey were (1.73
µg/g) greater than those in Maryland (<1.07 µg/g). Mean
hepatic Hg concentrations
were significantly higher in turtles from brackish water (1.28 and 1.27
µg/g) than from freshwater (<0.90 µg/g), but showed no
difference in mean kidney concentrations, 0.39-0.56 µg/g. Mean hepatic Zn concentrations were significantly higher in samples from
brackish water (50.38 and 38.95 µg/g) than from freshwater (<30.68
µg/g), but for kidney only differences were observed between males from
brackish water in New Jersey (10.51 µg/g) compared to all samples from
Maryland (<9.60 µg/g). Nickel,
detected in at least 80% of all samples, had significantly higher kidney
values from turtles from brackish water (1.24 and 1.07 µg/g) than those
from freshwater (<0.45 µg/g). In the liver, Ni was significantly lower in freshwater males from New
Jersey (0.13 µg/g) than all other samples (0.24-0.99 µg/g). Lead
and Cd were found in <50% of samples, at means <0.30 µg/g
for both tissues. |
4. |
Adult
snapping turtles collected in 1987 from Oak Ridge, Tennessee (N=12), and
Bearden Creek (N=9), a reference site 5.23 km upstream were analyzed for
radionuclide and Hg
contamination (Meyers-Schöne et al., 1993). Mean Hg
levels at the Oak Ridge site were significantly higher in both the
kidney (1.30 µg/g wet weight) and muscle (0.17 µg/g) than at the
reference site (0.34 and 0.10 µg/g, respectively). |
5. |
A
total of 37 snapping turtles collected from the Big River in the Old
Lead Belt of Missouri were analyzed for Pb
tissue levels and blood chemistry (Overmann and Krajicek, 1995). Two
collection sites were upstream of the Desloge tailings pile (one within
the Old Lead Belt and one outside) and one site was downstream. The
downstream site tended to have higher Pb
values than upstream sites for tissues sampled, and significantly higher
values for liver, blood, carapace, and bones. The site outside the Belt
had the lowest concentrations for each tissue. Mean Pb
concentrations (µg/g wet weight) for the three study locations ranged
from: 0.126-0.201 muscle, 0.166-0.292 brain, 0.177-0.490 liver,
0.280-2.514 blood, 0.977-33.013 carapace, and 1.015-114.563 bone. |
6. |
Snapping
turtle eggs were collected from 39 clutches in 10 locations on the St.
Lawrence River and its tributaries in Canada in 1989 and 1990 (Bonin et
al., 1995). Five eggs from each clutch were pooled and analyzed for
organochlorines and Hg, and
pools from similar localities were averaged. Mercury was detected in all samples analyzed with means
ranging from 0.050-0.180 µg/g wet weight. |
7. |
From
1989-1991, Hg
concentrations determined in snapping turtle eggs collected from five
study locations in the Great Lakes basin and St. Lawrence River were
0.14 µg/g wet weight (Bishop et al., 1998). |
IV. |
Petroleum |
|
No
residue data available |
V. |
Other |
1. |
Mean
radioactivity in bone ash
of two snapping turtles collected in Mississippi in 1970 was 218 pCi/g
(Holcomb et al., 1971). |
2. |
Snapping
turtles were collected from freshwater areas in the South for analysis
of the exoskeletal burden of Sr-90
(Jackson et al., 1974). Two individuals from Florida had an observed
range of radioactivity of 4.2-16.3 pCi/g of bone ash and two individuals
from Georgia had a range of 52.0-119.6 pCi/g. |
3. |
Adult
snapping turtles collected in 1987 from Oak Ridge, Tennessee (N=12), and
Bearden Creek (N=9), a reference site 5.23 km upstream, were analyzed
for radionuclide and mercury contamination (Meyers-Schöne et al.,
1993). Mean radionuclide liver levels for Oak Ridge and Bearden Creek,
respectively, were 0.174 and <0.0037 Bq/g wet weight Cs-137,
and 0.0517 and 0.0037 Bq/g Co-60.
In the muscle tissue, Cs-137
means were 0.396 and 0.0037 Bq/g. Mean levels of Sr-90 were 16.5 and <0.18 Bq/g in the bone and 16.6 and
<0.18 Bq/g in the carapace. All radionuclides were significantly
higher in the Oak Ridge site. |
Snapping
Turtle Contaminant Response Data |
|
I. |
Organochlorine Contaminants |
1. |
Snapping
turtle eggs collected immediately after oviposition from Algonquin
Provincial Park and 4 locations in the Great Lakes between 1986 and 1989
were analyzed for hatching success, incidence of deformities, and
contaminant concentrations (Bishop et al., 1991). A total of 202
clutches were artificially incubated for the study of embryos,
hatchlings, and hatching success. Lynde Creek and Cootes Paradise, which
were the sites most contaminated by organochlorines, contained the
highest incidence of deformities, including deformities of the tail,
hind legs, head, eyes, scutes, forelegs, dwarfism, yolk sac enlargement,
and missing claws. The most common deformity, occurring at all sites was
abnormality of the tail. Hatching success was lowest in Cootes Paradise
with the mean number of unhatched eggs/egg ranging from less than 0.1 to
greater than 0.4 between 1986-88. Algonquin Park, the least contaminated
site, showed the greatest hatching success with the mean number of
unhatched eggs/egg less than 0.1 each year. PCBs were the chemical most strongly associated with
deformities and hatching success, though the presence of other chemicals
in the eggs was a confounding factor. |
2. |
From
1989-1991, snapping turtle eggs from seven study locations in the Great
Lakes basin and St. Lawrence River, and Algonquin Provincial Park
(reference site) in north-central Ontario were collected and
artificially incubated (Bishop et al., 1998). Incidence of abnormal
development (including curled, bent, twisted, or absent tail; shortened
or absent legs or digits; deformed eyes; recessed lower jaw, reduced
body size; undeveloped carapace; presence of absence of scutes; and
unresorbed yolk sac) increased significantly with increasing
concentrations of polychlorinated
aromatic hydrocarbons, particularly PCDD
and PCDF, yet was not
correlated with TEQs in
eggs. The percentage of unhatched eggs, due to infertility or early
interruption of embryonic development, ranged from 0-10% for all but a
single clutch in which 40% of eggs failed to hatch. EROD and cytochrome
P4501A activities were significantly higher in liver of hatchlings from
Lake Ontario compared to the reference site. Porphyria was not observed
in turtles from either site. |
3. |
Three
snapping turtles were anesthetized, and intestinal mucosa, cloacal
bladder, kidney, and liver were incubated with 0.53, 5.3, and 53 µM DDT
for 30 min to measure ATPase inhibition (Phillips and Wells, 1994).
At 53 µM DDT, total
(Na+, K+,Mg2+)-dependent ATPase
activity was inhibited by approximately 52%in the intestinal mucosa,
45%in the cloacal bladder, 25% in kidney, and 38% in liver. |
4. |
In
1995, sex differentiation and reproductive endocrine function was
studied in adult snapping turtles from organochlorine-contaminated sites
in Southern Ontario (de Solla et al., 1998). The ratio of precloacal
length to the posterior lobe of the plastron (PPR), the value which is
normally indicative of sex, was significantly smaller in males from
three contaminated sites in the Great Lakes than males from the
reference site. A significantly larger proportion of males from one of
the contaminated sites had a PPR that overlapped with that of females
than PPRs of males at a reference site, confounding identification of
sex based on secondary sexual characteristics alone. Little change was
observed in plasma 17 ß-estradiol or testosterone concentrations. |
5. |
Snapping
turtle eggs collected in 1996 from uncontaminated sites in Algonquin
Park, Ontario were subject to topical application of DDE at doses selected to simulate concentrations found in the
Great Lakes (0.52-65 µg/5 µl ethanol) or estradiol-17
(positive control) (Portelli et al., 1999).
Eggs were incubated at a male-producing temperature.
Though eggs treated with estradiol did produce females at this
temperature, eggs treated with DDE
did not effect sexual differentiation at any exposure level. It was concluded that DDE,
at levels that are currently found at the Great Lakes, does not cause
feminization of snapping turtles during embryonic development. |
6. |
Snapping
turtle eggs were collected from 3 sites in Ontario, Canada, for
artificial incubation in June 1998 (de Solla et al., 2002). The three
sites were Hamilton Harbor; number of clutches=14 (heavily
contaminated), Akwesasne Mohawk Territory; n=3 (moderately contaminated)
and Algonquin Provincial Park; n=14 (reference site). Differences in
sexually dimorphic morphology were found between contaminated and
uncontaminated sites. Alterations in secondary sexual characteristics
occur in early development, suggesting transfer of organochlorines
from exposed females to offspring. |
II. |
Cholinesterase-Inhibiting Pesticides |
|
No
response data available |
III. |
Trace Elements, Metals, and Metalloids |
1. |
Blood
plasma analysis was performed on snapping turtles collected during the
summers of 1981 and 1982 from brackish and freshwater sites high in
metal contamination in the Hackensack Meadowlands in New Jersey and
relatively uncontaminated freshwater sites in Maryland (Albers et al,
1986). Turtles from Maryland had significantly higher ALAD and
significantly lower hemoglobin than turtles from brackish waters in New
Jersey, and significantly lower albumin, glucose, and total protein than
turtles from freshwater in New Jersey. None of the differences were
thought to indicate physiological impairment related to contaminants. |
2. |
A
total of 37 snapping turtles collected from the Big River in the Old
Lead Belt of Missouri were analyzed for Pb
tissue levels and blood chemistry (Overmann and Krajicek, 1995). Two
collection sites that were upstream of the Desloge tailings pile (one
within the Old Lead Belt and one outside) tended to have lower Pb
levels than one site was located downstream. Blood indices measured were
hematocrit, hemoglobin, and plasma glucose, osmolality, and Cl, and were
found not to differ between capture locations.
|
3. |
An
adult male snapping turtle presented to the Tufts Wildlife Clinic in
Grafton, Massachusetts had a Pb
concentration in blood of 3.6 µg/g and was diagnosed with Pb
poisoning (Borkowski, 1997). A Pb
sinker was recovered from the intestine and Pb
concentrations declined to undetectable levels after 6 weeks with
chelation therapy. |
IV. |
Petroleum |
|
No
response data available |
V. |
Other |
1. |
Six
snapping turtles were collected from a polluted stretch of the Kalamazoo
River, Otsego, Michigan in 1965 (Gibbons, 1968). Turtles were aged using carapace lengths and annular ring
lengths. The oldest turtle
was 15 years old. Mean
carapace length increased by an average of 32 mm/yr for the first 6
years, although the growth rate declined after the first year. |
2. |
Snapping
turtles were collected from a marsh at Great Meadows National Wildlife
Refuge, Concord, Massachusetts in 1976, which received 4.0-5.5 mg/l P
from sewage treatment plant effluent (Graham and Perkins, 1976).
Mean growth rate, measure by carapace length, was 26 mm/yr.
The two oldest individuals, which were 7 years old, grew by 26
mm/yr for the first 6 years, and then grew 48.2 mm in their most recent
year. The growth surge was
attributed to a dietary switch to larger prey such as waterfowl.
|
3. |
Adult
snapping turtles collected from Oak Ridge, Tennessee (N=12) in 1987 were
found to have significantly greater levels of radionuclide and mercury contamination, and 3.2 times as many
breaks in DNA strands compared to those from Bearden Creek (N=9), a
reference site 5.23 km upstream (Meyers-Schöne et al., 1993). |
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