The Vital Importance Of Turtles
In the field of wildlife conservation, the flashier and/or cuddlier animals usually get the most attention – tigers, pandas, elephants, and gorillas, for example. This is bad news for animals that most of us usually ignore, like the humble turtle. Despite being incredibly important animals that are facing unprecedented threats to their population, turtles get very little attention in mainstream conservation efforts. This paper sought to explain some of the ways turtles are important to their ecosystems, and hopefully encourage people to take the threats to these reptiles more seriously.
The first way in which turtles affect their ecosystem is perhaps the simplest: they make up a large part of it. This isn’t a metaphor: turtles make up a significantly higher percentage of an ecosystem’s biomass than most other animals. This is primarily due to their ability to achieve high population densities. In some habitats, pond slider turtles can number over 2000 individuals per hectare. Removing such a high percentage of an ecosystem’s biomass can have severe negative effects, perhaps restructuring the ecosystem entirely.
Turtles also regulate the energy flow of a given environment. Turtles redistribute energy in multiple ways, such as by being a food source for predators. In addition to being prey themselves, their eggs are food for many animals. Sea turtles lay their eggs on land, but only 27% of the energy in those eggs actually returns to the ocean as hatchlings. The rest stays on land and provides energy to the organisms that dwell on it. Beach vegetation benefits from the minerals that are released by the breakdown of eggshells and the bodies of unfortunate hatchlings. This vegetation keeps erosion in check, and a decline in sea turtle population could result in a decline in the number of beaches.
Turtles are also important consumers. Alligator snapping turtles function as apex predators, and Aldabra and Galapagos giant tortoises are the primary herbivores in their habitats. Specialized predators like the hawksbill and leatherback sea turtles keep their prey’s population in check. Finally, many herbivorous and omnivorous turtles consume and deposit seeds, which then germinate and grow into full plants. Some turtles are the only known distribution mechanism for certain plants, like the relationship between the eastern box turtle and the mayapple.
In addition, turtles – especially tortoises – function as environmental engineers. The gopher tortoise is one such example. They are prolific diggers, constructing elaborate burrows underground. These burrows are used by other animals, either in a symbiotic relationship with the tortoise, invading and displacing the tortoise, or moving in after the tortoise moves out. These burrows are so important that the gopher tortoise has been described as a keystone species, such that a decline in its population would have the potential to collapse entire ecosystems. Even sea turtles can shape their ecosystems: loggerhead turtles have a unique foraging strategy that greatly increases the breakdown of mollusk shells and other sediment, which affects seagrass growth.
Even in death, turtles are essential. Because of their long lifespans and high bone content, their bodies contain high concentrations of minerals like calcium. Herbivorous turtles like the gopher tortoise are important to the calcium cycle of an ecosystem, as they accumulate a high amount of the mineral in life and release it slowly in death. This trait can be useful to humans as well, as turtles can be used to monitor waterway pollution.
As animal advocates, we have to go beyond the easily marketable animals. Tigers, polar bears, rhinos, and pandas are all important animals that are worthy of protection, but so are more humble and unassuming animals like the turtle. By ignoring these animals, we reinforce a societal belief that these animals are either not in any danger or not worth protecting. By expanding awareness of the importance of all animals to their habitats, we can encourage a broader view of conservation in the general public. All animals are important and worthy of protection, and animal advocates should bring more awareness to those who have been overlooked by mainstream ecological organizations.