Narrative:

Because the authorities have allowed the iguana population to grow to a level where; more than a nuisance; they are a safety issue for flight operations. These animals are not originally from this country; and ATC tells us that they are a protected species. I don't know if that is a fact; but what I know is that they are a safety issue. Their eradication from the airport premises would not affect their overall population; as there are so many of them around the island that they threaten to eradicate other species themselves. Vehicles are on the runway chasing iguanas as we are getting ready to land. Followed ATC instructions to go around.

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Original NASA ASRS Text

Title: AN ACR CREW APCHING TJSJ WAS ISSUED A MANDATORY GO AROUND BECAUSE OF OPERATIONS PERSONNEL CLEARING IGUANAS FROM THE RWY.

Narrative: BECAUSE THE AUTHORITIES HAVE ALLOWED THE IGUANA POPULATION TO GROW TO A LEVEL WHERE; MORE THAN A NUISANCE; THEY ARE A SAFETY ISSUE FOR FLT OPS. THESE ANIMALS ARE NOT ORIGINALLY FROM THIS COUNTRY; AND ATC TELLS US THAT THEY ARE A PROTECTED SPECIES. I DON'T KNOW IF THAT IS A FACT; BUT WHAT I KNOW IS THAT THEY ARE A SAFETY ISSUE. THEIR ERADICATION FROM THE ARPT PREMISES WOULD NOT AFFECT THEIR OVERALL POPULATION; AS THERE ARE SO MANY OF THEM AROUND THE ISLAND THAT THEY THREATEN TO ERADICATE OTHER SPECIES THEMSELVES. VEHICLES ARE ON THE RWY CHASING IGUANAS AS WE ARE GETTING READY TO LAND. FOLLOWED ATC INSTRUCTIONS TO GO AROUND.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.