Piti Bomb Holes – Piti Bay & Western Shoals

10m Max

15-30m Vis

shore

Site Overview

Piti Bomb Holes is a unique reef formation consisting of natural depressions in the reef flat that create coral-lined pools teeming with marine life. These bowl-shaped formations, carved into the limestone reef platform over thousands of years, provide sheltered environments where coral growth is particularly dense and fish life concentrates in remarkable abundance. The shallow depth of 2 to 10 metres and calm protected conditions make this one of the finest snorkelling and introductory diving sites on Guam. Each bomb hole functions as a miniature reef ecosystem, with its own community of butterflyfish, parrotfish, anemonefish, and damselfish that thrive within the coral-walled enclosures. Green sea turtles are regularly encountered grazing on the reef flat between the depressions. The site is part of the Piti Marine Preserve, which has ensured healthy coral populations and abundant fish life through decades of protection. The underwater observatory at nearby Fish Eye Marine Park provides non-divers with a window into the same vibrant reef ecosystem, making this an ideal destination for mixed groups of divers and non-divers. The marine preserve status of this area has resulted in fish biomass levels significantly higher than adjacent unprotected reef areas, demonstrating the effectiveness of community-based marine conservation in tropical island environments. The bomb hole formations also serve as natural settlement traps for coral larvae, promoting ongoing reef growth and biodiversity within each depression.

Dive Briefing

"Enter from the shore access point and swim out to the reef flat where the bomb holes begin at approximately 3 to 5 metres depth. Each depression is coral-lined and hosts a concentrated community of reef fish. Work your way from one bomb hole to the next, observing the different fish communities and coral formations in each. The depressions range from 2 to 8 metres deep, with the deeper holes hosting larger fish and more diverse coral growth. Green turtles are commonly seen on the reef flat between the depressions. Maintain excellent buoyancy throughout as the coral coverage is dense and the shallow depth leaves little margin for error. The site is excellent for practising buoyancy skills in a rewarding environment. Exit via the same shore entry, being mindful of other snorkellers in the popular area. Total dive time is typically 50 minutes or more at these shallow depths. The deeper bomb holes at the outer edge of the reef flat host the largest coral formations and the most diverse fish communities, making them the priority targets for divers with adequate bottom time available during their dive."