Temperature’s Crucial Role in Crocodile Conservation

Caring for and breeding crocodiles is a highly temperature-critical business. Like all reptiles, crocodiles are ectothermic, which means they rely on external sources of heat to regulate their body temperature. 

Maintaining the right temperature and humidity levels impacts everything from their metabolism and digestive system to their immune function. Furthermore, temperature is critical to their reproductive success, influencing their cycles, egg development, incubation, and hatchling health. 

To find out more about how to cater to the complex temperature needs of reptiles, we turned to the UK’s leading specialists in crocodile care. 

The UK’s Only Crocodile Zoo

Crocodiles of the World is the UK’s first and only crocodile zoo. Founded by lifelong crocodile conservationist Shaun Foggett, their mission is to inspire respect and understanding for crocodiles through education and conservation. 

Temperature is one of the most essential elements that make Crocodiles of the World such an exceptional exhibit, but most importantly a comfortable home for over 150 crocodiles, reptiles, and mammals. 

We visited the zoo and spoke to Jamie Gilks, Section Leader of Lizards and Invertebrates, about how they monitor and control temperatures to maintain happy reptiles whilst also contributing to their conservation programme. 

Crocodile Climate Control 

With multiple types of temperature measurements required to keep reptiles happy, no single type of thermometer can do it all. The keepers use Therma-Hygrometers to monitor the air temperature and humidity, infrared thermometers to measure the surfaces below their heat lamps, and thermal cameras to assess the temperature distribution in the enclosures alongside the body temperature of the animals. 

One of their most important thermometers, Jamie tells us, is their Thermapen Classic thermometer. Most commonly used by chefs, keepers at Crocodiles of the World use them to check the pool water temperatures in the enclosures. “There’s heartbreak amongst the keepers if one of them breaks or stops working,” Jamie says. “They’re real workhorses, though. We’ve had to replace a few over the years, but it’s no fault of the equipment; human error around water means sometimes they go for a swim.”

The temperatures for each enclosure are thoroughly planned to ensure their optimal comfort and happiness while providing natural fluctuations similar to those they would experience in the wild. They check these temperatures at least twice a day. 

“I think what’s nice is that the buildings are greatly affected by our outside weather,” Jamie says. “We still have that element of randomness that you would in the wild where you could have an occasional hot day.”

As much as the keepers manage the zoo temperatures, Jamie stresses the importance of always giving the animals the choice to adjust their body temperatures through warmer and cooler spots in the enclosures. This is why heat lamps are a common feature for crocodiles and other reptiles. 

The visible happiness and well-being of the reptiles at the zoo is a testament to the attention given to their climates. Incorrect body temperature is usually characterised by lethargic, sluggish behaviour, but every enclosure was alive with activity. “It’s all about temperature,” Jamie says. “They’re just active in and doing what they should.”

Temperatures and Breeding

Conservation is key to Crocodiles of the World’s mission, and one of the most important ways they do this is through their highly successful breeding programmes. This has seen them become the first UK zoo to breed multiple endangered and vulnerable species of reptiles, including Siamese crocodiles and Galapagos tortoises. 

Two types of temperatures impact their breeding programme: the temperature of the reptiles’ enclosure and the incubation temperature of the eggs. 

The air temperature in the enclosures is key because it determines whether they will choose to breed. Increasing the air temperature triggers their breeding seasons while decreasing it ensures they have much-needed rest, replicating the natural seasonality these animals would experience in the wild.

Jamie describes how they realised they were initially keeping their Galapagos tortoises a bit too warm, which meant they were not breeding. Now, through increased monitoring and being more regimented with seasonal change, they’ve successfully bred Galapagos tortoises, which was a first for a UK zoo and incredibly important for gaining an understanding of the behaviours of this endangered species. 

“The reason we’re so successful with breeding programmes, especially when it comes to crocodiles, is because they are kept in optimal conditions,” Jamie explains. “And that comes down to temperature.”

Temperature-Dependent Sex Determination

The temperature at which reptile eggs are incubated can influence the gender of the hatchlings in certain species. This phenomenon, known as temperature-dependent sex determination (TSD), varies among reptile species. For crocs, males are produced in warmer temperatures and females in colder ones. However, if you go warmer than the male temperature bracket, you actually produce females again. 

A temperature difference of as little as 1-2 °C can impact the hatchling gender, which sadly means that global warming is impacting the natural gender ratio of some reptile species, such as turtles. 

The benefit of TSD for conservationists like Crocodiles of the World is that they can manipulate the incubation temperatures to produce male or female eggs. In zoos, they may not get the same temperature gradient as in the wild, which means they could end up with whole clutches of males or females unless they intervene. “Because we’re quite precise, we have a good success rate in getting the right balance,” Jamie says. The incubators are carefully monitored using therma-hygrometers to ensure the optimal conditions for the egg’s survival are maintained. 

Happy Crocs, a Positive Future 

Temperature monitoring is critical to ensuring the survival, happiness, and future of crocodiles and other reptiles. Crocodiles of the World showed us how they go beyond the basics of simply keeping reptiles within their optimal ranges and provide a thoughtfully planned and finely-tuned climate that is tailored not only to each species but also to their residents as individuals. 

What makes this unique zoo such a worthwhile visit is not just to enjoy the incredible welfare of the animals but also to support their fantastic breeding programme. Their success, partially attributed to careful temperature monitoring and control, is preserving species for future generations to enjoy. Jamie concludes: “I like to think of zoos as the ark you hope you never need to use. But, unfortunately, the world is far from perfect. Zoos, and the knowledge gained from their conservation and breeding efforts, are being called upon more and more to help preserve vulnerable and endangered species in the wild.” 

You might also like:

Managing Heat Stress in Firefighters with Modern Temperature Technology

Helping Rich Goodwin Reach New Heights with His Aerobatic Biplanes

Using Bluetooth Thermometers to Streamline Airline Catering

Top image: Nile crocodile at Crocodiles of the World.