The Trustees worked cooperatively and conducted multiple studies to assess resource injuries caused by the spill and to determine restoration needs. The results of this work are summarized in the Final Restoration Plan and Environmental Assessment Plan: Volume 1 (Ecological Injuries), a Final Supplement to that plan, and the Final Restoration Plan and Environmental Assessment: Volume 2 (Human Use & Recreational Injuries).

The Trustees determined that oil affected the following resources, or their uses:

Ecological Injuries

Mangroves
Trustees used ground surveys, aerial photography, and impact studies to determine the extent, nature and duration of the injury to mangroves. They found that approximately 5.5 acres of mangroves (primarily red mangrove (Rhizophora mangle), black mangrove (Avicennia germinans), and white mangrove (Laguncularia racemosa)) on Eleanor Island, Little Bird Key, and an unnamed island in Boca Ciega Bay near John’s Pass, were moderately to heavily oiled.
Studies: The 10 August 1993 Tampa Bay Oil Spill: Injury Assessment for the Mangrove Keys Inside John’s Pass: Update of Findings through January 1996, June 21, 1996.

Seagrasses
Trustees used aerial photography, exposure surveys, and community analyses to determine the area of seagrass injured and estimate the recovery rate. Trustees found that heavy to moderate oiling of seagrass beds (primarily turtle grass (Thalassia testudinum), manatee grass (Syringodium filiforme), and shoalgrass (Halodule wrightii ), occurred in Boca Ciega Bay near John’s Pass and southward. Approximately 2.5 acres of seagrasses in this area experienced moderate to heavy oiling, and were ecologically impaired for some time.
Studies: Assessing (Seagrass) Faunal Impact, June 1994.

Water Column
Trustees used computer-modeling techniques to estimate the extent of the water column injury. During the course of the spill, the oil slick traversed approximately 300 square miles of open Gulf waters and 27 square miles of bay waters. As it did, fractions of the discharged oils were dispersed into the water, and droplets of it were entrained in the water column. This contamination of the water column had the potential to affect exposed fishery stocks and planktonic organisms.
Studies: Final Report, Analysis of Water Samples from the Tampa Bay Area Following the August 10 Oil Spill, November 15, 1993.

Birds
Three hundred and sixty-six (366) birds were recovered and processed by a temporary bird rescue and rehabilitation facility established at Ft. DeSoto Park to treat birds during the response. Bird injures included direct mortality as a result of oiling and ingestion, or stress from capture and cleaning. In addition, experts indicated that a significant number of the affected birds were not captured or recovered. Thus, the total number of injured birds was assumed to equal the number of birds rehabilitated (366) x 2, or 732 birds. Indirect injuries to birds – resulting from the disruption of nesting and foraging activities and a loss of habitat – were addressed within the assessment and restoration planning for mangrove and salt marsh injuries.

Sea Turtles
According to response records, the federally endangered green sea turtle (Chelonia mydas) and the threatened loggerhead sea turtle (Caretta caretta), their nesting beaches, nests and foraging areas were oiled or disrupted by cleanup operations (although special spill response efforts were directed toward protecting these sensitive resources). Injuries to these species included mortality, oiling, reduced hatching success, and disturbance.

Salt Marshes
Trustees used ground surveys and aerial photography to determine the extent, severity, and duration of the injury to salt marshes. Approximately 0.75 acres of salt marsh vegetation (primarily smooth cord grass (Spartina alterniflora) in soft-bottom communities) sustained some level of injury due to oiling, primarily within Boca Ciega Bay from north of John’s Pass to Gulfport.

Shellfish Beds
Trustees used data from spill response surveys and independent field evaluations to determine the area and duration of the injury to shellfish beds. Surveys documented that 0.22 acres of oyster beds associated with intertidal areas of Elnor Island, Rookery, and Little Bird Keys, were destroyed as a result of smothering by the spilled oil or physical disruption caused by removal and cleanup activities.

Bottom Sediments
Trustees used response surveys to estimate the exposed bottom sediment area, and evaluated effects using scientific literature. The Trustees estimated that submerged oil patties or mats covered at least 1.34 acres of subtidal sediments just off Pinellas County beaches as well as seagrasses, mud flats and deeper areas of Boca Ciega Bay. Observations of several species of crustaceans indicated that the oil caused injury to subtidal organisms.

Beach (Physical Injuries)
Trustees used response records to determine the amount of sand removed during cleanup. At least 13 linear miles of sandy shoreline along Gulf beaches were oiled during the spill, from Redington Shore southward to Fort DeSoto Park and at Egmont Key. At least 39,827 cubic yards of sand were removed from public beaches during the cleanup, potentially diminishing the capacity of the beach to resist erosion or protect coastal areas from storms.

Lost Recreational Uses

Shoreline Recreation
Based on data and information available from response and preassessment phase activities, the Trustees determined that the initial oiling and associated cleanup of beaches from Redington Shores to Egmont Key (at least 13 linear miles) effectively closed affected recreational beaches for up to 3 weeks. Periodic re-oiling of some of these beaches thereafter occurred after storms (when offshore deposits of submerged oil were remobilized) and resulted in additional disruptions in use. Recreational losses caused by the oiling of area beaches was quantified by measuring the normal level of recreational use of these beaches for a similar period under non-spill conditions.

Recreational Boating
The presence of oil and spill response activities restricted or disrupted access to portions of lower Tampa Bay and Boca Ciega Bay. Boats were prohibited from certain areas during the response. Many boats located at marinas or docks were also prevented from leaving dockside and some popular boat ramps in the spill area were closed, or their use limited, for some period of time.

Recreational Shellfishing
As a result of the discharge, shellfish beds in lower Tampa Bay and Boca Ciega Bay were closed to fishing. In lower Tampa Bay, an estimated 14,424 acres of shellfish beds were closed for 45 days, and near Mullet Key an estimated 14,105 acres were closed for a total of 112 days.