Vocabulary

Non-Indigenous Species

The Mediterranean is home to species from elsewhere, known as Non-Indigenous Species (NIS). These animals, plants, fungi, or microorganisms are observed due to changes in their natural distribution range, caused by natural or human factors.

Invasive species

If a Non-Indigenous Species proliferates uncontrollably, disrupts local ecosystems, or causes ecological, economic, or health-related damage, it is then classified as an invasive species.

Native species

A species occurring within its natural historical or current range and potential dispersal area.

Endemic species

A native species that has evolved over time into a distinct species found only in a specific geographic area.

Non-Indigenous Species

A species introduced outside its natural range by human action or naturally.

Invasive species

A Non-Indigenous Species that establishes itself permanently, reproduces, and spreads to the point of threatening ecosystems, native species, or human activities.

Pathways of introduction in the mediterranean

Maritime transport

Ballast waters, seawater intake systems, biofouling (organisms attached to hulls)

01

Marine corridors and waterways

Lessepsian migration via the Suez Canal, artificial corridor connecting the red sea to the Mediterranean

02

Aquaculture

Escape of non-indigenous farmed species, introduction of associated organisms or disease spread

03

Recreational boating

Passive transport of species via hulls, equipment, or residual water

04

How do these species establish themselves in the mediterranean?

For a Non-Indigenous Species to successfully establish itself in a new environment such as the Mediterranean, multiple ecological and biological criteria must be met. According to research, three key factors favor its establishment:

Absence or scarcity of natural predators

Without natural regulators (predators, parasites, or competitors), the species can proliferate uncontrollably.

Availability of food resources

An abundant and accessible food source enables the species to survive and reproduce.

Ability to adapt to local conditions

Species capable of tolerating variations in temperature, salinity, or other abiotic parameters have a higher chance of establishing themselves.

Climate change plays a major role here: Rising temperatures in the Mediterranean are making the environment more hospitable to tropical or subtropical species, such as Fistularia commersonii or Siganus rivulatus.

Arcuatula senhousia
MINKA © xavi salvador costa CC BY-NC

To find out more…

NIS
New sightings

Callinectes sapidus

NIS
Under surveillance