Reproductive Ecology and Body Burden of Resident ... - The Love Lab

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Task 3: A Histological Examination of the Ovaries of Pacific Sanddab, Citharichthys sordidus, Captured at Two Oil Platforms and Two Natural Sites in the Southern California Bight In this study, we collected Pacific sanddab at four sites in the Santa Barbara Channel, southern California. These sites include two platforms, B and Gilda, and two natural comparison sites, one located about 8 km offshore and southeast of Platform B “Rincon”) and the other off the northeast corner of Santa Cruz Island. After capture, the fish were placed on ice and several hours later were measured (total length, cm) and the ovaries fixed in 10% formalin. In the laboratory, a section of each ovary was removed, dehydrated in ethanol of ascending concentrations, embedded in paraffin and serial sections were cut at 5µm using a rotary microtome. Sections were mounted on glass slides, stained with hematoxylin followed by eosin counterstain and each section was examined for the presence of: (1) hydrated eggs for upcoming spawning; (2) vitellogenesis (yolk deposition) in mode of smaller eggs for subsequent spawning; (3) postovulatory follicles (evidence of recent spawning); (4) follicular atresia (degenerating oocytes). Atresia was characterized as minor (
there was substantial variability in concentrations of a number of elements among fishes, there was no consistent pattern of higher concentrations of any element at either platforms or natural sites. Second, we examined the otoliths of these fishes to determine if there might be a distinctive “signature” created when platform fishes are bathed in the hypothesized polluted waters. Our results indicate that the elemental composition of kelp rockfish otoliths and Pacific sanddab otoliths differ between the two habitat types—the sampled platforms and natural sites—and geographic areas. However, we found that elemental concentrations in otoliths were not consistently higher from platform habitats. Barium, a residue released into the environment from platform activities, occurred in higher concentrations in otoliths of kelp rockfish collected from midwater depths at platforms than from natural rocky reef areas. In contrast, the concentration of barium in benthic-dwelling Pacific sanddab was lower from platforms than from natural soft sediment habitat sites. We found that variability in otolith element concentration among sites was not related to the concentration of the elements in our seawater samples from kelp rockfish and sanddab habitats. Third, we characterized the reproductive capabilities of Pacific sanddabs living around platforms and natural sites to assess for possible indirect effects of the hypothesized contaminants on reproduction. We found no consistent pattern of significantly higher levels of severely atretic eggs among either platform or natural site sanddabs. x
Page 1: Pacific Outer Continental Shelf Reg
Page 4 and 5: Disclaimer This report had been rev
Page 6 and 7: TECHNICAL SUMMARY Study Title: Repr
Page 8 and 9: interactions between total length (
Page 10 and 11: REPRODUCTIVE ECOLOGY AND BODY BURDE
Page 12 and 13: tometry. The determination of selen
Page 16 and 17: Task 1: Whole-body Concentrations o
Page 18 and 19: Study Area and Methods The study ar
Page 20 and 21: Sample Collection Fish species cons
Page 22 and 23: to confirm the calibration status o
Page 24 and 25: variation in elemental concentratio
Page 26 and 27: Table 2. Summary of fish vital stat
Page 28 and 29: Table 3. Variation in total length,
Page 30 and 31: Cadmium. Cadmium concentrations in
Page 32 and 33: Iron. Iron concentrations in the th
Page 34 and 35: Nickel. None of the three fish spec
Page 36 and 37: Strontium. None of the three fish s
Page 38 and 39: Vanadium. Kelp bass and kelp rockfi
Page 40 and 41: came from an oil platform (PL4, 3 o
Page 42 and 43: Table 4. Comparisons of selected tr
Page 44 and 45: Literature Cited Allen, M.J., D.W.
Page 46 and 47: May, T.W., J.F. Fairchild, J.D. Pet
Page 48 and 49: Task 2: Otolith Elemental Signature
Page 50 and 51: sider the ecology of species of int
Page 52 and 53: Table 1. Characteristics of the 18
Page 54 and 55: an undetectable amount of an isotop
Page 56 and 57: Table 2. Two-way ANOVA comparing tr
Page 58 and 59: G 5.0 Kelp rockfish H 20 Platform N
Page 60 and 61: Table 4A. Correlations of predictor
Page 62 and 63: CDA generated a model discriminatin
Page 64 and 65:
Pacific sanddab otolith elemental s
Page 66 and 67:
A 0.034 Pacific Sanddab B 0.10 Plat
Page 68 and 69:
Table 7. One-way ANOVA comparing tr
Page 70 and 71:
Table 9A. Correlations of six predi
Page 72 and 73:
Kelp rockfish Otolith (element/Ca (
Page 74 and 75:
Discussion Results from univariate
Page 76 and 77:
of non-drilling associated discharg
Page 78 and 79:
ture and salinity on otolith elemen
Page 80 and 81:
Miller, J. A and A. L. Shanks. 2004
Page 82 and 83:
Appendix 2. Seawater element-to-cal
Page 84 and 85:
Appendix 3. Seawater element-to-cal
Page 86 and 87:
Task 3: A Histological Examination
Page 88 and 89:
Table 1. Details of Pacific sanddab
Page 90 and 91:
Figure 2. A) Ovary of Pacific sandd
Page 92 and 93:
Literature Cited Allen, M. J. 1982.
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