Invasive Species: Brown Tree Snake
Stability of the Ecosystem
By: Rafael Ramirez, Alejandra Mendoza, Stephanie Rico, and Brian Serrato
- Historically, the brown tree snake has no natural predators which allows their population to grow. Also, the snake population continues to grow because some lizard species reproduce quick enough which keeps the brown tree snakes to not out eat their food supply.
- The native birds and lizards of Guam are known to eat insects to keep those populations in check, but with the drastic decline of the populations, the insect population will surge. As a result, diseases carried/ spread by these insects may also increase.
- additionally, the native birds and fruit bats of Guam are a crucial part of seed dispersal/pollination for vegetation. However, with most of these species now extinct, seeds are not being spread and plants are not being pollinated, the natural succession of the forest may be at risk as well. If this happens, every animal species in this ecosystem may eventually die out, including the brown tree snake.
Why?
- Their relatively small size has made these species to be vulnerable and they also lack the defenses needed to survive since snakes are not the natural predators of these bird, lizard, and bat species.
- In addition, Snakes will eat birds' young and eggs which also contributes to the population decline since they don't reach adult age in order to reproduce.
Interesting facts
- The brown tree snake has not only affected the ecosystem but the economy as well. For example, the brown tree snake species has been responsible for the island-wide blackouts which has resulted in the loss of one to four million dollars each year.
- Additionally, Guam is losing its tourists which may cause major economic stress since they mainly rely on the tourism dollars.
- It is predicted that if the brown tree snake establishes itself in Hawaii, .5 to 1.5 billion dollars will be lost each year
Examples of extinct animals
Guam
Trouble in the Ecosystem:
Little Marianas Fruit Bat
- Location:3,300 miles West of Hawaii, 1,500 miles east of the Philippines
- Geography: Forests and Cliffs in the north and savannas and river valleys in the south
- Known for its Biodiversity
Since the arrival of the Brown Tree Snake...
- There has been an incredible decline in Guam's biodiversity. For example, the disappearance of almost half of Guam's native birds( half are extinct, six are nearly gone, and three exist in small numbers) and lizards
- Also, the bat population has also been affected resulting in two of the three bat species to go extinct.
Pacific Sheath-Tailed Bat
Invasive Species: Brown Tree Snake
- Introduced to: the island of Guam, A U.S Territory
- When: After World War Two
- How: navy vessels
- Origin: Indonesia
- Scientific Name: Boiga Irregularis
- Features: Nocturnal, Big Head, huge eyes, slender body
- Effects: Poses a threat to Guam's biodiversity and stability