Let’s look at what I call “new recruits”, or mother sea turtles that laid a nest for their first time. I didn’t consider the DNA results for years 2009 to 2013 as DNA testing only began in SC in 2009, and in 2010 on HI (Hunting Island). Since a mother turtle may nest every two to three years, true new mothers (new recruits) may not be apparent on HI until 2014. First, some data and then a few new recruit stories.
On HI, new recruits peaked in 2019 at 33 or 46% of the unique females. The number has not dropped below 20 new recruits since that time. In 2014 and 2015, the new recruits numbered only 8 each year. The number of new recruits as a % of unique females on HI has trended down since 2016. It is not that new recruits have fallen off, it is that the number of unique females visiting HI is growing. That’s good news.
I think what is important is not the new recruit trend but the number of new recruits that present themselves over a longer period. The period from 2014 to 2018 averaged 17 new recruits a year on HI. From 2019 to 2023 that number jumped to 25. That is an average increase of eight new recruits per year and that is just for HI and not for all of SC. Pretty good!!
We might also ask “when did the unique females first lay a nest (i.e. when were they new recruits)?” I did this for the unique females that nested on HI in 2023. Almost 80% (61 out of 77) of the unique mothers in 2023 laid their first nest somewhere in the northern region over the 10 year period from 2014 to 2023. While there were 21 new recruits in 2023 on HI alone, another 40 unique females laid their first nest, not necessarily on HI, during the 2014 to 2022 period. For example, a whopping 15 new recruits from 2020 returned to the beach in 2023 to lay a nest on HI. Over time, it is these relatively new recruits that are fueling recent growth.
The growth in new recruits is critical to loggerhead recovery as long as the “newbies” exceed those that, unfortunately, “retire”. As nesting in all of SC has trended up over the last 10-15 years, I say job well done.
So now, three mother turtle stories from HI in 2014. The first one is sad. New recruit CC007720 laid a nest on HI on May 31st with 100 eggs. Unfortunately, she has not been seen anywhere in the database since that one nest! Either she moved onto beaches without DNA testing, had a short time on this earth, or was an older mother who previously nested pre-2010 and served her species well.
Then there is new recruit CC007446 who was first seen on June 17, 2014. Her first couple of nests that year were depredated. She nested in 2014, 2018 and 2021 – four and three years in between nesting seasons. Maybe she will be back this year. Since late June 2018, she has nested exclusively on Harbor Island. However, she likes roaming St. Helena Sound, nesting four times on HI, nine times on Harbor, one time each on Otter and Bay Point Islands.
Then there is CC000543 who was first seen in 2010. She is not necessarily a new recruit, however she is not your average mother sea turtle either. She is also fairly loyal to HI but has hit Fripp and Pritchards Islands. This unique female is one of the most productive HI has. She has laid 41 nests since she was first seen in 2010 and that doesn’t include three possible missed nests. DNA analysis reports she laid nests in 2010, ’12, ’13, ’15, ’16, ’19, ’20, ’22 and 2023. That’s nine years out of 14, with either no years off, or one to two years off. Her nesting this frequently defies the general rule that loggerheads lay nests every 2-3 years. I guess this mother sea turtle didn’t read the rule book.
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