DOI: 10.15468/twdvdk
title: South Australian Hardshell Marine Turtles - Tourists, Strandings, or Residents? (aggregated per 1-degree cell)

description: Original provider:
Aub Strydom

Dataset credits:
Data provider: Aubrey Strydom; Originating data center: Satellite Tracking and Analysis Tool (STAT); Project sponsor or sponsor description: Aub Strydom

Abstract:
Hardshell marine turtles - most commonly greens and loggerheads are occasionally found alive or dead on South Australian beaches.&lt;br&gt;Often they are not in good condition, and require rehabilitation.&lt;br&gt;Paddy is an exception, and was fat and healthy, measuring 89.5cm and weighing 83kg.&lt;br&gt;She was found at Middleton Beach 16th March 2023 in a large amount of seaweed, which may have restricted and exhausted her. &lt;br&gt;She arrived at Adelaide Zoo on St Patricks Day 17th March 2023 - hence the name Paddy.&lt;br&gt;She spent the next 2 weeks being examined and cared for by the Vets and Nurses at Adelaide Zoo.&lt;br&gt;After discussion with Marine Science turtle experts in Western Australia and Queensland - the decision was made by Marine Parks SA to release her on 31st March close to where she was found - Rapid Bay was chosen - away from the weed that may have slowed her swimming.&lt;br&gt;Her satellite tracker was borrowed at very short notice from the Marine Science section of the WA Parks and Wildlife, and has shown her first head North up Gulf St Vincent, where she reached the head on 13th April.&lt;br&gt;She basked on mudflats near Port Wakefield on 14th April, and for a second time on an isolated beach 27km north of Port Adelaide's Outer Harbour on 22nd April, after gradually swimming back down from the top of Gulf St Vincent.&lt;br&gt;She spent more than a week from the 24th April in the Port Adelaide estuary, and soon after 1st May swam across the Gulf to be 5km off the coast of the Yorke Peninsula on 5th May and began heading south until 10th May 2023, when she rounded the heel of the Peninsula at Troubridge Shoal Lighthouse, and began swimming west.&lt;br&gt;She followed the southern coast of Yorke Peninsula at about 17km a day, then swam NW at 51km a day, crossing 140km of deep water in lower Spencer Gulf in less than 3 days to get to the coast of Eyre Peninsula on 19th May 2023.&lt;br&gt;On 23rd May her temperature was 15.2C. She moved up into Franklin Harbour Marine Park for over a week. This bay is rich in seagrass, and she had plenty to forage on here.&lt;br&gt;On June 7th she was 60km north of Franklin Harbour, heading up the middle of Spencer Gulf, and began using an area on the eastern side about 7-25km south west of Port Pirie on the 9th June.&lt;br&gt;From 9th to 30th June to she remained here, foraging in an area 20km long and between 1km to 3km offshore. Then she slowly moved North towards Port Augusta, foraging south of the city for a month. Her coldest overwinter temperature was here at 8.2C, but for most of July was in the range 11C to 13C. From mid August she was hanging between the car and rail bridge in Pt Augusta, and in late August to mid September her temperature went up to stay between 15.2C and 15.5C.&lt;br&gt;During October she averaged around 17C, ranging 15C to 19.2C, having moved halfway down the eastern side of Spencer Gulf to the southern end of Moonta Bay, remaining mostly in nearshore shallow waters. &lt;br&gt;She turned north west here on 24th October, and reached the eastern side of the Eyre Peninsula again on the 1st November, moving up to spend over a week just north of Whyalla till November 14th.&lt;br&gt;By 16th November she was back up in the very upper end of Spencer Gulf, with just 3km of sea left before the start of the arid lands.&lt;br&gt;For November her temperature ranged between 17.2C and 22.2C, and by the end of November she had moved 70km south to again be around Whyalla.&lt;br&gt;She then traveled down the coast to arrive at Port Lincoln and spend most of December there. Her last location was on 30th December and the final signal came on 1st January 2024. The battery was still good, so some possibilities include that she damaged the tracker, scrubbed it off, or it became so bio-fouled that the saltwater switch no longer operates. &lt;br&gt;&lt;br&gt;The results from her DNA test suggest she most likely hatched in the Southern Great Barrier Reef - her size suggests about 35 years ago. &lt;br&gt;Her travels suggest she is a local SA resident forager, and not passing through, and she is the first hardshell turtle known to overwinter in South Australian waters, and the first to be tracked foraging in the two Gulfs.&lt;br&gt;
 This dataset is a summarized representation of the telemetry locations aggregated per species per 1-degree cell.