MMS ENVIRONMENTAL STUDIES PROGRAM: ONGOING STUDIES
MMS OCS Region: Pacific
Title: Reproductive Ecology and Body Burden of Resident Fish Prior to Decommissioning
Actual Costs: $535,000.00 Period of Performance: FY2005-2009
Conducting Organization: University of California-Santa Barbara (Contact: Milton Love)
MMS Contact: Dr. Ann.S.Bull
Description:
Background
In order to analyze the environmental consequences of decommissioning platforms on local or regional fish populations, the sources of young fish recruiting to those populations and the general pollution load carried by reproducing adults at platforms must be known. This is especially true when the platforms are known to harbor large numbers of resident reproducing adults from species that are regionally depleted and being considered for listing under the Endangered Species Act. This study will be phased with two separate work tasks. The first will develop a technique to judge the degree to which movement and recruitment of rockfish occur from platforms to local and perhaps regional populations from platforms off California. The second will relate the level of contaminants in platform resident rockfish to the local and regional background quantity and variability of contaminants found in the same or similar age species.
Objectives
Task 1 Objectives

1. To determine which discreet, detectable trace element or suite of elements are present in seawater at platforms and not present in other local water bodies.

2. To determine if the platform trace element(s) is detectable as a microchemical signature in rockfish larvae and not detectable in rockfish from control sites; and,

3. To determine the degree to which otolith chemistry varies as a function of water chemistry.

Task 2 Objectives

1. To survey and determine the nature and extent of contaminants present in various tissues from platform resident fish and shellfish.

2. Compare platform resident body burdens and contaminants to those found in similar size and species of fish and shellfish at various locations away from platforms.

3. Relate the level of contaminants in platform species to the local and regional geospatial background quantity and variability of contaminants in fish and shellfish.

Methods
The methods for sample collections necessary for Tasks 1 and 2 are essentially the same and can be performed for both studies at the same time. Samples for Task 2 can separated and stored while Task 1 continues.

Task 1 Methods

1. Using SCUBA diving and standard collection devices acquire sufficient numbers from several species of rockfish larvae and/or juveniles from 1-2 platforms and several control sites.

2. Collect water samples several times during the year to characterize the aquatic environment at the same sites and analyze bulk chemistry.

3. Analyze samples (extracted otoliths and water) with either inductively-coupled plasma mass spectrometry (ICP-MS) or atomic emission spectroscopy (ICP-AES) for Ba, Zi, Ca, Pb, Cu, Sr, B, Li, and Ni.

4. Address the degree to which otolith chemistry varies as a function of water chemistry and spatial scale using multivariate statistical analyses; and,

5. Analyze if species differences affect otolith uptake of trace elements and use discriminant function analysis to test the degree of separation of otoliths by element, geographic location, and species.

Task 2 Methods

1. Using SCUBA diving and/or standard collection devices such as traps or trawls collect or acquire sufficient numbers of the same species and size class of shellfish and adult rockfish, benthic, and pelagic fishes from platforms, shell mounds, and from control sites away from platforms.

2. Remove and freeze/store appropriate muscle, gall bladder, liver/hepatopancreas green gland, gonad, and nervous system tissues for analyses.

3. Analyze tissue samples for PAH’s and/or metabolites, poly chlorinated biphenyl’s (PCB’s), dichloro-diphenyl-trichloroethane (DDT) and/or metabolites, and trace and heavy metals; and

4. Compare the contaminant load of platform resident species to the pre-existing geospatial background of the areas near offshore platforms.

Importance to MMS
The fate of spent offshore platforms and pipelines off California has been a subject of considerable debate, much of which is focused on the potential importance of the fish at these facilities to the local and regional populations. Knowledge of the importance of resident, reproducing rockfish at offshore facilities to the depleted Pacific rockfish stocks is essential for fully evaluating the various options proposed for decommissioning California’s offshore oil platforms. Reproductive impairment, as seen by histological examination, has direct implications for regional fish populations. If there is no apparent ovarian impairment but contamination is present, then there are important indirect implications for larval fish development and juvenile survival.
Current Status:
On-going. The first field collection efforts were extremely successful with 100% of samples successfully collected from both platforms and natural sites. The ovarian histology is completed, the microotolith chemistry is proceeding, and the contaminant analyses have begun.
Final Report Due: 08/05/2009
Publications:  
Affiliated WWW Sites: http://www.lovelab.id.ucsb.edu/index.html
Revised date: November 30, 2006
ESPIS

ESPIS - All completed ESP Studies:
Full Text, Online, Right Now!
 Environmental Studies Program Information System