Interactions

            Loggerhead sea turtles are both predators and prey in the marine food web. They are omnivores, meaning they eat both plants and animals, however they usually prey on animals. Loggerhead turtles are well known for their big heads and extremely powerful jaws, therefore they are equipped to consume hard-shelled prey such as horseshoe crab (Duermit, 2007). Other species actually benefit from the loggerhead turtles eating hard-shelled organisms because the left over shells can serve as a calcium source (Duermit, 2007). Loggerhead turtles’ diet also consists of jellyfish, sponges, shellfish, shrimp and squid (Department of Energy and Environmental Protection, 2013). Unfortunately during reproduction, the loggerhead eggs are highly vulnerable and can serve as a food source for predators such as raccoons or red foxes. In their adult life the turtles can be prey for organisms such as sharks, and birds (Duermit, 2007; Department of Energy and Environmental Protection, 2013).
         There are even some organisms, both plant and animal, that actually live on the shell of the loggerhead turtles and are known as epibionts (Harding et al., 2011). Loggerhead turtles can serve as a host to parasitic organisms like the marine turtle leech (Ozobranchus margoi) (University of Pennsylvania, 2004). Parasitism is a symbiotic relationship in which one organism, the parasite, benefits at the cost of another organism, known as the host, that they are living on or inside of (Campbell et al., 2008). The marine turtle leech actually latches onto the loggerhead’s exposed body and uses them as a food source as well as a place to lay eggs. If a turtle becomes too infested, it will stop feeding and potentially lead to mortality (University of Pennsylvania, 2004). Unlike the marine turtle leech, many of the organisms that live on the loggerhead are not harmful towards the turtle and just use them as a place to live. Some examples are gastropod molluscs, which are large snails, from the family Muricidae (Harding et al., 2011) and algae (Duermit, 2007). An organism that has recently been discovered to be an epibiont is the invasive species Veined Rapa Whelk (Rapana venosa), that use the loggerhead turtles to migrate to new coastal areas and disperse their eggs. (Harding et al., 2011). 
        Sadly, the loggerhead turtle population is currently on decline. Humans play a very large role in this drop. The leading threat to the turtles are them accidently getting caught in fishing gear (NOAA Fisheries, 2013). Loggerheads have been caught in a variety of different types of fishing gear like drift nets or set nets either by chance, swimming into the net or even by preying on fish that are trapped in the nets (Echwikhi et al., 2012). While in the net, the loggerhead often begins to suffer from apnea, which is a temporary suspension of breathing, causing 60% of the total captured turtles to die due to drowning (Echwikhi et al., 2012). Another human caused factor leading to the decline is debris left in the ocean. The turtles have been known to entangle themselves in the debris or even digest it (NOAA Fisheries, 2013). Humans have also been harvesting the loggerhead turtle in areas such as the Bahamas, Cuba and Mexico (NOAA Fisheries, 2013).

 

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