In the next slide we see an upland area that is the remains of an aborted dredge and fill project for a housing development that never took place. It has been invaded by Australia pine. Notice how out of place these trees look compared to the native vegetation.

Here we see a 1951 aerial of what has come to be known as Crawford Island, near the end of where 4^th Street South is now. The middle part of the island is covered in very low saltmarsh vegetation, with just a few small mangroves around the island’s perimeter.

Now we see the exact same area as it appeared in 1969, after dredge and fill had taken place for houses on Yawl and Sloop Drive. Canals were dug and the spoil was used to create uplands for houses. Spoil was also deposited on marsh vegetation, destroying the wetlands habitat in the middle of Crawford Island for what would have been another housing development. Notice the dark shadows from Australian pines. I was visiting that island at this time and remember exploring among the young trees in the newly created uplands - a disturbance ripe for invasion by Brazilian pepper and Australian pine..

In the next slide we see the same area as it appeared from the air in 2004. The dark spots that you see are the shadows of large Australian pines.

These artificially created uplands, resulting from dredge and fill for housing developments that were never built and mosquito control canals, created habitat that is perfect for invasion by invasive   non-native species such as Australian pine, Brazilian pepper, carrotwood, melaleuca, and Schefflera.

And finally we see the 2004 aerial with a plat map laid over the top of it showing the proposed housing development that was never built.

So what is it about the Thousand Islands that makes them so susceptible to invasion by these five non-native species? All five of these trees have one characteristic in common – they are all tropical plants. Read more about this on the next page Here.