Greetings from the rainforest! This week, I'll be talking about porcupines; more specifically, the Mexican hairy dwarf porcupine! When I first came to Costa Rica, I was surprised that there were porcupines endemic, or native, to this area. I'd only known about the North American porcupine, which is only found as far south as northern Mexico. I'm sure you've seen photos of this species, with their long fur and quills. The Mexican hairy dwarf porcupine is found from Mexico to Panama, and looks quite different than its northern relative. About four and a half pounds as an adult, they're covered in short brown fur with patches of yellow quills throughout their body that are most concentrated around their face. As a mostly arboreal species, they have a long, prehensile, naked tail that aids them when climbing through trees. Many rainforest mammals have prehensile tails, including porcupines, opossums, kinkajous, and several species of monkey. This is an interesting example of convergent evolution, a word used in biology to describe when animals from different lineages evolve similar features. One example of this is the evolution of flight in both birds and bats: the ancestor of birds and bats couldn't fly, yet modern day species of both lineages have evolved flight to access food and avoid predators. In the rainforest, the thick canopy makes arboreal locomotion the easiest way to take advantage of the fruit, insects, and prey found in the tree tops, and it also allows animals to avoid large terrestrial predators. Moving through branches and trees is much easier if your tail can grasp branches and assist in climbing. Therefore, many rainforest animals in different families, including primates, rodents, carnivores, and marsupials, have evolved a similar tail.
There is currently one porcupine at Kids Saving the Rainforest named Patrick. He was found near a hotel, and after a search of the area failed to find his mother, he was brought to Kids Saving the Rainforest and raised in the nursery. He has since been moved into rehabilitation so that he can learn skills to survive in the wild and to undo his imprinting. Imprinting is a common problem with animals from the pet trade and those raised in nurseries, and it refers to unnatural dependency on and desire to be around humans. If you release an imprinted animal into the wild, they will seek out human companionship as soon as possible, which could lead to them getting recaptured for a pet, injured, or even killed. The methods used to raise and rehab animals try to avoid imprinting, but it is sometimes inevitable that they become too used to humans through their frequent interactions necessary to provide for them the best care possible. This happens often in species that are susceptible to imprinting such as porcupines, and Patrick has had a problem with attention-seeking behaviors. Imprinted animals go through an extensive rehabilitation process where their contact with people is restricted to allow their natural wild instincts, including a fear of humans, to return. Therefore, when Patrick was moved into rehabilitation, he was placed into a cage inside boot camp, so that he would have as little contact with humans as possible. When I arrived, Patrick would come out of his nest box as soon as he heard us approaching his cage. He would frantically climb on the tree limbs and sides of the cage, trying to climb onto you as you changed his food and water. Although every instinct told me to hold him and give him attention, I knew that it was in his best interest to dislike and fear humans. Additionally, a porcupine is not exactly the type of animal that you want crawling over you and cuddling up with you!
In order to undo his imprinting, we would give a harmless but unpleasant deterrent when he approached and reached out to climb onto us. These include squirting water in his face, blowing in his face, or making a sudden sound like finger snaps or shushing. As bad as I felt about doing this, Patrick ensured that I felt even worse by climbing to a corner of the cage and whining to himself after he was chased off. Sometimes, doing what's best for the animals is unpleasant for both you and the animal in the short term, but it will ultimately ensure that they can live a life without cages in the wild.
Patrick has improved a lot recently, but he is still showing behaviors that indicated he is imprinted. To help with this and to allow him to learn more survival skills before being fully released, the clinic staff decided to release him from his smaller cage into the main boot camp area so that he would have a larger terrain to explore. Since porcupines are nocturnal, we released him in the late afternoon, closer to the start of his "day". We woke him up by tapping gently on his nesting box, then opening the door of his cage so he could walk out into boot camp. Hesitant at first, he climbed on top of the open door and spent a while looking around. Eventually, he climbed down and trotted out of his cage. As we expected, he immediately made his way to the three of us standing close by, determined to get the cuddles he so desperately wants. We spent a couple of minutes walking away from him (baby porcupines are thankfully not very fast!) until he got distracted by the sights and smells of the forest around him and ambled off into the bushes. Since then, we've seen him several times when feeding the sloths, and have always had to quickly walk away to avoid prickly porcupine cuddles. He still has a way to go before he is able to be released, but we were all very happy that he completed the next step towards freedom.
Miller, M. 2009. "Sphiggurus mexicanus" (On-line), Animal Diversity Web. Accessed October 02, 2019 at https://animaldiversity.org/accounts/Sphiggurus_mexicanus/