Galapagos Islands News

Over the centuries, many different foreign species have been introduced into the Galapagos Islands. Some have caused more ecological damage than others, and some have been easier to eradicate than others. Feral donkeys, for example, were relatively easy to remove from the Galapagos Islands because they are large herbivores, predictable and easy to see. In general, animals are easier to remove from the Galapagos Islands than plants, the seeds of which can be difficult to find. Many insects have also made their way to the Galapagos Islands: one such species is the Mediterranean Fruit Fly (Ceratitis capitata), first recorded in 2008. Since then, aggressive efforts to remove it have had some success.

The Mediterranean Fruit Fly

The Mediterranean Fruit Fly is a small insect which has an extremely negative effect on agriculture, particularly fruit. Originally from Africa, this tough little bug has spread into many areas of the world, devastating agriculture industries as it goes. All fruit flies lay their eggs in fresh fruit. When the eggs hatch, the larvae eat the fruit, causing it to spoil and be unfit for human consumption.

Why it’s so bad for Galapagos

No introduced species is welcome in the Galapagos Islands, and the fruit fly is no exception. It may surprise outsiders to learn that Galapagos has an important local fruit industry. There are four towns in the Galapagos Islands, and many of the people there have grown their own fruit for generations. In Galapagos, the Mediterranean Fruit Fly attacks several different fruits, including the cactus fruit (which is consumed by humans) and the Manzanillo (which is poisonous). A fruit fly infestation could severely damage the locals’ ability to feed themselves with locally-grown fruit. Also, some local fruit is purchased by hotels, restaurants and cruise ships to serve to tourists: if it all had to be brought from the mainland, prices would go way up.

The Mediterranean Fruit Fly in Galapagos

The fruit fly was first reported on San Cristóbal Island in May of 2008. In spite of an aggressive and strict quarantine, the fly was soon found near Puerto Ayora as well. Almost immediately a task force bent on exterminating the fruit fly was set up, bringing together several agencies including SIGCAL (the Galapagos quarantine program), the National Park, the Charles Darwin Foundation and CIMEI (The Galapagos species control program).

Efforts to Remove the Mediterranean Fruit Fly

The new task force threw everything it had at the fly in order to eradicate it before it became entrenched in the Galapagos Islands. Crops were fumigated, traps were set, education of the local population was established and experts were consulted. Monitoring has also begun on Floreana and Isabela in case the fly spreads yet again. The fruit fly infestation is hardest on almond trees, which are hosts for its reproductive cycle. Almond trees are therefore sprayed more regularly, fallen fruit is taken away and destroyed, and the ground beneath the trees is regularly raked to disrupt the fruit fly breeding cycle.

A Success Story?

Results have been very encouraging. The all-out effort to exterminate the Mediterranean Fruit Fly is not yet a complete success, but the constant monitoring of traps has shown that populations of the pest are considerably down. In December of 2009 it was reported that for fourteen consecutive weeks on Santa Cruz and eight consecutive weeks on San Cristobal, not a single fruit fly was found in any of the monitoring traps, although those strings were both broken later, proving that the fly has not yet been eradicated. Still, the results have researchers and rangers very excited about the possibility of eliminating them once and for all. Efforts are ongoing.