300 to 400 sea turtles have turned up dead off the coast of El Salvador, and scientists are on a mission to find out why.
Locals had already spotted turtle carcasses floating in El Salvador’s Jiquilisco Bay, 13 kilometers from the shore, as early as October 28. Most of the remains were already decomposing by the time they were found. Authorities in El Salvador didn’t make the massive die-off public until they announced it on Twitter on November 2.
So far, however, details on the die-off have been scarce. We don’t even know what species the turtles were, if they all belonged to one species or to several. Jiquilisco Bay is a natural reserve wherein a number of different species live--hawksbills, green turtles, leatherbacks, and olive ridleys. El Salvador’s ministry of environment said that they were collecting samples from the turtles’ remains, but have not yet found a possible cause of death.
Photo by MARN El Salvador via Twitter
This isn’t the first time that a massive die-off involving turtles has happened in the waters off El Salvador. Similar events occurred in 2006 and 2013. In the 2006 die-off, about 119 turtles were found dead. The 2013 die-off, meanwhile, occurred between September and October. Over 200 turtles were found dead. Authorities said that in both of these cases, red tide caused the turtles’ death.
A red tide is actually a harmful algal bloom. This happens when colonies of algae, which are simple marine plants, grow out of control. The algal blooms make the water look red, hence the term “red tide”. These colonies then produce toxins that can be harmful to humans and marine life if consumed.
Of course, not all algal blooms turn out to be toxic and deadly. In fact, most algal blooms are beneficial. However, some algae can produce toxins that can be harmful and even fatal to animals, including turtles.
So is red tide to blame for the most recent turtle die-off in El Salvador? Authorities haven’t yet released an official cause of death, since toxicology reports are still pending. While it’s likely that red tide is what killed all these turtles, we can’t really be certain until official reports are released.
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