Snake control in Ibiza and Formentera (Part II)

28 January 2023

NOVA FALCONS, COMPANY SPECIALIZED IN THE CONTROL AND CAPTURE OF SNAKES

Snake control in Ibiza was started as a pilot test in 2014 by the Consell de Eivissa. During the pilot phase, different control methods were tested: from the use of dogs to different types of traps that led to the current system.

The plans for making the traps are distributed free of charge by the Consellería de Medio Ambiente. For those who wish to make their own traps, a direct link is available below.

At Nova Falcons, we have been using the same model with some small modifications, related to size and environmental isolation. The basis of how it works is very simple: it is a wooden box with two compartments divided from each other. One contains one or more live mice, which act as an attractant for the snakes. The other, which is empty and inaccessible to the mice compartment, has a trap door that the snakes can only open from the outside. Once inside, they cannot get out, nor can they access the mouse compartment. Both compartments have lids at the top so that both the mice and the snakes that are caught can be handled.

Captura de serpientes Ibiza y Formentera

Snake control is a system that works with live bait, so it requires minimum care and attention from the person in charge of the snake traps. This live bait are mice, but not taken from the field, they are the typical mice used as live food, and due to their genetic characteristics, they do not have any type of fear or propensity to suffer stress or any other type of physical or psychological suffering derived from life in captivity.

Water, food and material to make a warm, dry nest (e.g. straw) should be available to the mice at all times. As rodents, it is very likely that this material will have to be replaced from time to time, as they tend to shed it. Another aspect to consider is rainfall. If the trap is made following the pattern of the front made of mesh, this must be taken into account, since if the trap is flooded or the inside of the trap becomes clogged, the mouse will probably die of hypothermia. In our case, what we have done is to modify the design to ensure that even if water gets inside, it drains perfectly, so that our snake traps can be left in place all year round, without worrying about the weather and the welfare of the rodents.

Installation of the traps

Where snake traps are placed influences the results that will be obtained. The easiest way is to place them where snake sightings have been made: attached to bushes, dry stone walls, etc. If you are checking to see whether there are snakes in the area, the basis is the same: place them where they are most likely to be looking for shelter or food. When setting a new trap, allow a small amount of time. Snakes come to the traps primarily through smell, and as the smell of the rodents camouflages the smell of people, wood and the products used to make the traps, the traps become more effective.

If a trap does not work for weeks, the best thing to do is to change its location, but following the same principle: it should be placed in a place where the snakes can naturally come to look for food or shelter. It is important to remember that the months of greatest activity are from June to August, although from April to November, it is possible to capture snakes. Therefore, it is perfectly logical and normal that no snakes are caught during the winter months: as a general rule, they will be dormant and hibernating.

trampa

Catch management

No one who likes nature and living beings in general is going to enjoy sacrificing a living being. All of us who are aware of the need to capture snakes in Ibiza and Formentera are so because of the seriousness they represent for the survival of certain species in the current ecosystems of Ibiza and Formentera. Therefore, having to cull every specimen that is captured is not a good thing: it is a purely objective necessity. A necessity that has to be carried out as quickly and bloodlessly as possible.

When removing the snake from the trap, it is important to bear in mind that they are quick, although they tend to withdraw into themselves at the outset. It may be advisable to use special tweezers or, failing that, to pick them up directly by hand, always protected by a glove. Although they are probably going to try to modernize, we should not worry about this: their teeth are tiny and do not contain any kind of poison. If you are not sure whether you can identify the species of snake inside the trap, then, as a precaution, it is always advisable to consult a professional.

It should be clear that the current entry route for horseshoe snakes and ladder snakes, as well as the occasional bastard snake (Malpolon monspessulanus), is none other than the importation of century-old olive trees for ornamental purposes. This entry is still active, so it cannot be ruled out that new species may arrive, which, in some cases, may be poisonous. Therefore, if we are not sure of being able to identify the species inside the trap, the safest thing to do is to consult a professional.

This article complements what has already been explained in "Snakes on Ibiza and Formentera", where we basically focus on making a brief presentation on the seriousness of the uncontrolled spread of the horseshoe snake (Hemorrhois hippocrepis), and to a lesser extent (but not without seriousness), of the ladder snake (Rhinechis scalaris), for the ecosystems of Ibiza and Formentera.

The famous and spectacular "blue lizards" of Formentera, one of the species seriously endangered by the spread of horseshoe snakes.