Remote archipelago off western Australia
I have been to these islands six times with three different ships; the first two times as Expedition Leader with Coral Expeditions, the next times as a biologist guide with Silversea.
The Montebello Island are located just north of Barrow Island, about 130 kilometres off the Pilbara coast of north-western Australia. They are most famous for being the site of a series of three atomic blasts by the British in the 1950s. One of these sites has a monument right at ground zero, right in the north of Trimouille Island. It is suggested you only stay here for a hour. There is a nice walk from the monument, over the ridge, and down to a large shallow lagoon. The islands are typical of arid Australia, with spinifex grasses and other desert plants.
The breeding birds include Wedge-tailed Shearwaters, Fairy Terns, and Roseate Terns. Nesting Ospreys seem to be on every island. There are many lizards here, although it is mostly the tracks that I have seen. There are rays in the shallow lagoon. The large ones may be the 'Round Ribbontail Ray' Taeniurops meyeni.
There is one special animal here; the Rufous Hare Wallaby ('Mala') was once widespread throughout arid Australia, but is now pretty much extinct on the mainland, except in some small fenced off areas. However, a population was introduced onto Trimouille Island, where they are common. If you walk from the main blast site monument in the northern tip of the island and towards the lagoon just a kilometre south, you have a good chance of flushing out these mammals from underneath the clumps of vegetation. Their tracks are everywhere in the sand and they seem common here.
The snorkelling, despite what you may read on some promotional websites, is not particularly good. There is tidal movement and not much coral reef growth. But at least there are no crocodiles!
The Montebellos were not opened up until recently. They are still remote and rarely visited, mostly only by recreational fisherman. Occasionally an expedition ship adds an extension to the long Kimberley trips, and stops in the island group during a western Australia coastal voyage down to Fremantle/Perth.