PIFSC Sea Turtle Longline Research EA June 1, 2009
entanglement. Although these are not expected events, mitigation measures to minimize the potential for adverse impacts are in place, and include shortened handling time and attempted resuscitation of comatose animals. Turtles are only handled for the amount of time necessary to complete sampling, measuring, examination, and/or tagging. Data from 135 previously tagged and released turtles from 1982 through February 2006 showed that no tagged turtles found stranded were determined to have died from capture-related activities (NOAA and NMFS 2006). Therefore, no injury or mortality is predicted to occur from capturing, handling, tagging, or sampling during any of the proposed research activities, and measures are in place to minimize the risk to the animals.
While turtle mortalities are not expected as a direct result of any of the proposed research actions, an additional safety mitigation and experimental design evaluation measure is in place such that should up to two turtle mortalities occur while a research activity is being conducted, all operations involving that activity would be immediately suspended pending review of the methods and procedures. While rare, single animal mortality may occur coincidental to, but not directly resulting from, the research activity due to prior individual injury, disease, or other condition(s) unrelated to the research activity. However, in the unlikely event that a second mortality should occur during the course of the proposed research activity, the experimentation would be halted to verify that experimental design is not a contributing factor.
Importantly, these impacts would have been expected to occur in the baseline as a result of normal fishing activity. In the proposed action scenario, it is likely that fewer animals will need handling because fewer will be caught as bycatch as compared to normal (i.e., non-research scenario) fishing operations.
Potential impacts of invasive procedures such as blood sampling and tagging on sea turtle individuals
For a complete understanding of sea turtle population dynamics and life history, it is necessary to identify individuals and obtain biological samples for biochemical evaluation. Turtles are tagged with pop-up satellite archival tags (PSATs) using standard techniques (Swimmer et al. 2002,
; blood samples are taken using a medical grade needle and syringe (Bolten 1999, Owens
. All methods used are performed by trained personnel and have been peer-reviewed and
used by sea turtle researchers worldwide. Blood sampling will not be taken from leatherbacks, as observers are not trained to do so. Unnecessary sampling on sick or injured animals will not be performed unless a veterinarian determines the animal is sufficiently healthy for samples to be taken. No mortality or adverse effects to turtles are expected from tagging or blood sampling.
The attachment of a radio transmitter (i.e. satellite tags) to the shell of a female sea turtle may appear to be obstructive to mating; however, this has been documented not to be the case. Females with satellite tags attached to their shell prior to the nesting season have been observed nesting, and examination of the nests after hatching indicated that successful mating/fertilization had occurred (NOAA and NMFS 2006). Additionally, transmitters continue to decrease in size as technology advances. The transmitters available for use today weigh approximately 0.1 – 0.2 kg and measure 6.5 cm x 3.5 cm x 2.5 cm. The small size of the transmitters reduces the likelihood that the animals’ ability to mate or swim will be adversely affected. PSAT tags have