Trapping

Trapping Meaning

Trapping is a centuries-old practice that has been used for both practical and traditional purposes. Today, it continues to play an important role in ecology, particularly in the management of wildlife populations. It is often used when animals need to be relocated due to human encroachment.

Trapping Laws

Trapping is a highly regulated activity in many jurisdictions, and strict laws govern the types of traps that can be used and the manner in which they can be deployed.

When used responsibly, trapping can be an effective and humane tool for managing wildlife populations.

Welfare standards may include the need to provide food, drink, and shelter inside the trap.

A trap can be either lethal or non-lethal, depending on its intended use.

Traps and Statistical Analysis

The right kind of traps (based on species, size, location, etc.) need to be paired with the correct statistical analysis techniques.

There are a variety of different statistical methods that ecologists can use, and the choice of method often depends on the type of data that is being analysed.

The Lincoln Index is a simple averaging formula used for estimation purposes once part of a population had already been caught. It makes use of trapping and release in two stages. It sums up the number of individuals caught in the first stage with the number of individuals caught in the second stage. Then, it divides the resulting number by the number of individuals caught in the second stage that already had marks (from having previously been caught).

Mean standard deviation (adding data items and then dividing by the total number), regression analysis (can be used to examine the relationship between tree height and diameter), and hypothesis testing (can be used to test the hypothesis that tree height affects diameter) are all valid techniques that are used in conjuncture with trapping.

Complex multivariate analysis techniques, such as Kendall's W, may be required when different data needs to be superimposed (meaning laying data on top of each other for better visualization), such as for soil biodiversity analyses.

Best practice in animal trapping

It is especially important to exercise care when setting up and handling animal traps. Considerations and best practice measures include:

• Minimal disturbance of the surrounding environment: reduced or no vegetation trampling, uprooting, loud noises, waste left behind, etc.

• Environmental conditions recording: making sure that the conditions in which the trap is set, and the animal is caught are recorded: sunlight, wind speed, precipitations, etc.

• Appropriate apparatus usage: making sure the specific instruments that help take quantitative measurements are functioning well, for example, pH meters, water turbidity meters, altimeters measuring altitude, handheld sonars for echolocation, etc.

• Risk assessment: identify the risks surrounding the person setting or examining a trap, and the animal being trapped.

Let's look at what can happen to a trapped animal in general.

Trapping Reasons

Reasons why trapping is necessary usually include the need to get or verify accurate wildlife data.

Information obtained from trapping (and trapping itself) can further be used to:

• Relocate wildlife
• Control population size
• Manage biotic or abiotic impacts on the environment

Placing of Traps

A quadrat of any shape, such as a circle, may be established, that can be as small as a few metres or as big as a few acres. Traps are placed within its perimeter. All caught animals this way are marked, until more marked ones are caught than unmarked ones.

If the animals are caught alive, but the researchers know the traps cannot be verified before the weather conditions are likely to change (the day-night cycle), the cages should be provided with thermoregulatory material, such as flax or cotton.

Types of Traps

All traps have specific limitations regarding the size of organisms they can catch and how many they will at the same time. It is often difficult to accommodate more than one organism in the same trap, but the more social or tolerant a species is, the better the chances to accommodate more in the same trap.

Insect Traps

All the following types of traps, except for spring traps, can be successfully used on insects. "Falling traps" and nets, as described below, may be among the most popular insect traps.

Pitfall Trapping

This can be a container or a cavity, dug inside soil or other materials, with an opening at the top, which collect organisms that fall in.

Tullgren Funnel

Tullgren funnel trapping is a method of trapping using a light source. It collects soil arthropods (members of the phylum Arthropoda, also known as insects) by exploiting their positive or negative response to light. A tullgren funnel consists of a glass funnel with a narrow inner neck, placed inside a larger container, such as a jar. The neck of the funnel is placed over a light bulb, which heats the air inside the funnel and causes the arthropods to move away from the light and fall into the container. Tullgren funnel traps can be used to collect a variety of small arthropods, including mites, springtails, and ants.³ This method is particularly useful for sampling soil invertebrates in the tundra and other areas where light is scarce.

Nets

Nets are a common tool used in wildlife trapping. They can be used to capture animals of all sizes, from small rodents to large mammals. Nets can be baited or unbaited, and they can be placed on the ground or suspended in the air. When an animal walks into or flies into a net, it becomes entangled and is unable to escape. Wildlife trappers often use nets to capture animals alive so that they can be relocated or studied.

Sweep nets, plankton nets (catching plankton-sized organisms), pond nets, or aerial nets (lightweight nets used to capture small flying organisms, especially insects) are easy tools to use for population capture and sampling, involving minimal risks to the organisms.

Mammal Traps

Some mammalian traps are designed to catch one specific species. Harp traps are specialised in catching bats. A set of very thin, perpendicular strings directs bats during flight into a funnel-like bag from which they cannot get out until the daytime when the trap will next be checked.

Spring traps tend to be used to catch mammals. Some other names are rubber-jaw traps, or padded traps. They have rubber instead of sharp teeth around the metal foothold, in order to avoid penetrating the animal's skin, albeit still being able to restrict it. They are powered by a spring that is pressure-sensitive. Such traps may usually restrict the blood flow in the caught limb and cause numbness. An animal should not be left caught in one for more than a day, due to the risk of self-harm.

Reptile Traps

Reptile traps can sometimes be tricky to set up. Great-crested newt traps in the UK, for instance, should be checked at least once daily and between a small two-hours window in the morning coinciding with the reptiles' movement! Additionally, cages are a good choice for catching live small and medium-sized terrestrial vertebrates. Cages offer some of the better welfare options available, such as the possibility of placing food, water and thermal matting inside.

Traps are a great tool for population sampling, but they must be calibrated or placed in ways which avoid hurting sensitive species. Too much power, light, heat, or similar behind a mechanism can lead to the stress and death of the caught organism.