Here is a very interesting article found online posted by the Division of Habitat and Species Conservation Invasive Plant Management Section of Tallahassee, FL.
Please take a minute to check the complete article HERE.
Below are some details taken directly from the article:
You might not think that here could be many similarities between and fish and a tree but there are more the you think. Both the Lion Fish and the Casuarina are labelled as invasive and perhaps by highlighting their similarities we will learn more about how they threaten the environments around them.
Predators: Extensive research is being undertaken to find a means of biological control for these two species. Scientist from the Bahamas (Which have been dealing with an exponential Lion Fish invasion since early 2000) are going to do field research in the Indian and Pacific oceans where these fish are from to study what keeps their population in check over there.
Similarly with the Casuarina scientists from Florida and other heavily casuarina-infested places are heading to it’s home-land in Australia to research what kind of insects could be used as a predator to keep the trees under control.
This article In Search of Biological Control Agents for the Invasive Australian Pine sums up what work is being done to find an adequate predator for the Casuairna.
Reproduction: The Lion Fish reproduction is sexual and involves external fertilization of eggs and a suite of complex courtship and mating behaviors. Males will aggregate with multiple females to form groups of 3-8 fish. Each female releases clusters of 2,000-15,000 eggs into the environment where they are fertilized by the male.
Australian pine does not rely on living organisms for pollination; it casts its pollen to the wind. Known as anemophilous pollination, the taller the tree the more effectively the pollen is broadcast to the female flowers. In the case for the Casuarina equisetifolia which thrives here in the TCI, It has male and female flowers on the same tree, meaning it self pollinates and produces seeds at an alarming rate. The seed has a membranous wing to aid its dispersal that can be either by wind or in water and a few species of birds eat and disperse the seeds.
Growth Rate:The embryo of the Lion Fish begins to form around 12 hours after fertilisation, with a developing head and eyes becoming apparent after 18 hours. The walls of the encasing eggs become invaded by microbes, and deteriorate around 36 hours after fertilisation, when the larvae hatch. Lion Fish reach sexual maturity within two years.
The Casuarina’s growth is most rapid during the first 7 years, and then declines. Maximum growth is reached in 20 years with a maximum life span of 40 to 50 years. In Florida, growth rates have ranged from 3 to 5 feet a year in the wild, to over 10 feet a year under cultivation. The fastest growth rate was reported from Barbados where a height of 30 feet was attained in 2 years.
Habitat destruction: the Lion Fish is a threat to our environment as it can eat up to its own body mass in one day. It hunts from dusk until dawn and researches have found up to 30 fish inside the bellies of captured Lion Fish. They are a threat to the delicate ecosystem here since they are eating the food that native fish would usually eat. Some reefs that were once teeming with fish are now left rather desolate after the Lion Fish population got out of hand.
The Casuarina similarly has adverse affects on the environment here since it displaces native vegetation. Native plants are out competed by the fast growing, very tolerant and invasive Casuarinas and as we loose our native vegetation we are also loosing the indigenous animals that feed off native plants and trees.
There are many more similarities between these two invasive species but the only difference is that we can actually do something about the Casuarina Invasion, however many scientist agree that as for the Lion Fish, it is here to stay and needs to be monitored very closely forevermore.
This tree was toppled in a hurricane but it hasn’t died. Notice how absurdly shallow the root system is – no part of it penetrated deeper than about 20 centimeters
Trying to reason with Hurricanes PDF document was created after hurricane Charley hit Florida in 2004. I have highlighted areas of interest to us here in the T.C.I and I encourage you to take the few minutes to read from page 4 onwards, especially if you plan on being properly prepared for hurricane season.
Below is a snippets taken from the article that describes a very similar situation we are facing here in the TCI as many residents jump to conclusions regarding the need to control this invasive tree.
There are many who feel that the Casuarina is at home here in the T.C.I and that controlling their population is bad. It seems that the known facts of how Casuarinas negatively affect native vegetation and invade the habitats of local wildlife has not changed perceptions; Perhaps the drastic threat to human-life during hurricane season might.
Photos below are taken from the PDF article stated above:
A quick google search of the following: ” Turks and Caicos Iguanas” will reveal just what kind of treasure we are blessed to have living in our country. Within the first line of the iguana’s description on wikipedia you can read the following:
“The Turks and Caicos rock iguana (Cyclura carinata) is a critically endangered species of lizard of the genus Cyclura that is endemic to the Turks and Caicos islands.”
The key word here is endemic, meaning “unique to”, meaning we are hosts to the ONLY population of this kind of rock iguana. All the more reason to protect it and raise awareness regarding its safety.
Last week we went out on our boat and noticed that there are many small Casuarina’s on Little Water Cay [better known as Iguana Island] which hasn’t always been the case. The Casuarinas on Water Cay have been present for many years creating a small ‘forest’ which blows Casuarina seeds downwind onto Little Water Cay.
Photo taken July 2011- Water Cay
If we do not control the Casuarinas on Water Cay the future for the Iguanas looks rather grim. The Casuarinas would eventually creep onto Little Water Cay where the largest percentage of the iguanas exist. Once established they will start to self seed more and more rapidly as saplings mature and release hundreds of thousands of seeds periodically, clearing out the local vegetation.
We have seen this process in many places throughout the TCI as well as having sufficient research conducted by scientists worldwide studying the Casuarina’s invasive characteristics. Therefore there is no doubt that these newly arrived Casuarinas will become the foundation for a Casuarina forest, slowly pushing out any of the local vegetation from which the iguanas feed themselves.
Photo taken July 2011- Water Cay
As we drove our boat along the coast line of Water Cay we noticed another one of our national treasures flying in the sky, the osprey. The bird continued to circle around in the sky scoping out the scenery for some food. As we watched it pass in between and in front of the Casuarina forest we noticed how the flimsy branches of the Casuarina bent back and forth with the wind, making them unstable and unsuitable for the osprey to land on. If the Casuarina population grows the ospreys will have fewer options for nesting and for perching themselves. Other larger birds face the same dilemma as the osprey.
Among other things the Casuarinas are also detrimental the to sand-stone coast line that runs along Water Cay. Their root system grow throughout the sand stone and when they topple over they inevitably break the sand stone lining provoking beach erosion.
If the Casuarinas take over Little Water cay [or Water cay in general] then the National Park that was put in place to protect the indigenous species will no longer serve its purpose. Their chances of coexisting with Casuarinas is unlikely.
To read more about the Turks & Caicos rock iguana click HERE
To see a complete list of indigenous birds Turks & Caicos click HERE
I came across this article with a simple Google search. It was published in August 2009 by a geography professor from the College of the Bahamas who later was an editor for a journal of science and went on to publish many books. His credentials are listed below and the article follows. If you would like to read the article on its original site click HERE
For those who would like a summary I took the time to highlight areas that relate to the TCI by underlining them.
Take a look at this picture taken from of whats left on the beach in Grand Bahama. There was once a sand dune that protected the shore line. The Casuarinas you see in the picture have in fact eroded the dune leaving the shore without shelter from prevailing winds or storms.
The Casuarina Controversy
by Neil Sealey
Neil Sealey was a geography professor at the College of the Bahamas from 1979 to 1995. He edited The Bahamas Journal of Science – published by Media Enterprises from 1993 to 2004 – and is the author of six books, including Tourism in the Caribbean (Hodder & Stoughton, 1982), Bahamian Landscapes (Macmillan Caribbean 2006) and Caribbean World (Cambridge University Press, 1992). He was also editorial consultant for Macmillan Caribbean’s 2000 edition of Caribbean Certificate Atlas.
It is unfortunate that a number of persons seem to have missed the point about the removal of casuarinas along our shorelines.
Correspondents, columnists and editors have all written recently in support of ‘saving’ the casuarinas along Saunders Beach. However, these are not being removed for any perverse satisfaction of denying people shade, a view of the sea, or the visual appearance of these large trees. It is simply a matter of preserving another natural resource, in this case the beach and adjacent property and infrastructure, and ensuring that our coastline is able to withstand storm waves in an era of climate change and sea level rise.
The reason the sea is visible through the trees is because the natural dune and its accompanying vegetation, as it exists at Orange Hill, Delaporte and Paradise Island at present (and many Family Islands), has been lost. Extensive scientific study in this country and elsewhere has established that casuarinas will prevent the growth of native vegetation resulting in the decline of the attendant sand dune and exposure of the coast to erosion. (see above picture)
This is exactly what has happened at Saunders Beach where, after hurricanes Floyd, Michelle and Frances, to name three storms, massive amounts of sand were carried across the road into the Shell station and elsewhere, and property all along this section was threatened by flooding.
This was the reason for the restoration of Orange Hill Beach, and since the provision of a bridge over the dune and some car parking space, the houses are relatively safe, and the beach wide and attractive with many local species of plants. A number of shade trees such as buttonwood and sea grape could be planted to replace the shade provided by the casuarinas, and more quickly some thatched gazebos could be built at little cost.
Unfortunately we can’t always have attractive sea views and safety together. Either we have a protective beach/dune system or we have a sea wall and revetment as is already in place along much of West Bay Street. Despite the letter writers, many people do welcome the proposals for Saunders Beach, much of which is an eroded rocky foreshore, only a small part in the west actually collecting sand at the present.
Beyond the visual aspect some writers have challenged the concept of casuarina-induced beach erosion. A Google search for ‘casuarinas beach erosion’ will provide some independent corroboration for this, notably in Texas and Florida. A recent Tribune editorial cited a 2007 study by Mangala de Zoysa from Sri Lanka that purported to justify casuarinas as a coastal protection plant.
The casuarinas at Hambantota City were planted behind an existing sand dune to provide a wind break, and it was the sand dune that protected the city during the tsunami. The author does claim that casuarinas trap sand and have encouraged the increase in the height of the sand dune in front of them, but does not explain how this has happened, and a causal correlation is certainly suspect.
Planting casuarinas in blocks behind dunes as means of increasing the coastal barrier is basically what is implied here, and actually bears no relation to the line of trees along Saunders Beach.
In fact a 2007 IUCN Report, Technical Guidelines for the Establishment of a Coastal Greenbelt in Sri Lanka, had this to say: The practice of planting monoculture coastal shelterbelts of Casuarina, especially in cyclone prone areas, however, did not appear to be effective wave barriers, and the current evidence indicate that a good wind shelterbelt mix should include shorter trees and shrubs, which when planted on sand dunes helped indirectly by stabilizing the dunes. Coconut palms can withstand the physical impact and salinity effects and reduce beach erosion, but they do not contribute to protecting areas behind them. (Both the Zoysa chapter and the IUCN report can be found on Google).
The aesthetic value of casuarinas to many people is not denied and is not an issue. The issue is the choice between long term protection of a ‘priceless national asset’ and its recreational use, as opposed to transient sea views along unprotected roads and continued beach degradation.
Picture taken on North Caicos, near the abandoned Prospect of Whitby hotel.
Many people think that the Casuarinas on North and Middle Caicos [or any other T&C island] are not a threat to our national habitat. Only time will tell if this is true, but the scientific and field research that has already been done and the examples set by our neighbors in Bermuda & Florida [most popular cases who have taken action against this invasion] should be enough to change those opinions.
The monetary cost of waiting for time to show us what kind of damage an invasive species can do will only increase each and every day/month/year as the Casuarinas spread. They do not need to be eradicated from the TCI since they have naturalized themselves here, but they do need to be controlled.
Lets not forget that they are most commonly known as the AUSTRALIAN Pine. Emphasis on “AUSTRALIA“. Why are we hosting/protecting the Australian Pine over our very own Almond tree, Coconut Palm, Clusia [locally known as the 'signature' tree], Lignum Vitae, Sea Grape, Tamarind, Geiger [Cordia] tree, Mahogany, Joe Wood, Tabebuia tree, Cabbage Palm and Thatch palm? These plants and trees ARE from here and the Casuarina is not.
On Saturday, March 19th, Turks and Caicos DECR Project Manager Bryan Naqqi Manco offered an invasive species workshop at the National Environmental Centre. The pictures below are taken from a great article written by Pepperkeystacie and they show just how fast these trees grow.
This first picture was taken on March 3rd 2008 in Middle Caicos:
This next picture was taken in December 2010 of the same tree:
Notice how the ground around the tree and boat has become covered in small Casuarina saplings. This scene will soon change into a forest if left without control.
Stacie quotes Naqqi: “If you have a Causarina on your property, the best step is to chop the tree down and poison the stump with roundup”. Naqqi explained the tree is closely related to oak and that there are many great uses for your now fallen tree.
In the article Stacie goes on to highlight the other top invasive plants in the Turks and Caios Islands namely ‘Cow Bush’ (Leucaena leucocephala), Scaevola Taccada and Brazilian Pepper (Schinus terebinthifolius) that are threatening the native vegation here. The Casuarina is number one on the list and therefore the most threatening invasive species.
Click HERE to view the article directly. Click HERE to visit the National Environment Centers website.
The picture below shows invasive species samples from left to right #1 Causarina, #2 Cow Bush, #3 Scaevola, and #4 Brazilian Pepper.
To read the article click HERE
This article highlights how Hawaii (as well as other regions) has already taken the appropriate steps to protect it’s natural environment. Hawaii is dealing with the same issue that we have here in the Turks and Caicos Islands and is a brilliant role-model for us to replicate its progress when dealing with this invasive non-native species.
The article states the following:
A recent (1999) Executive Order by the President of the United States recognizes the nationwide problem of harmful invasive non-native species. According to a recent U.S. Congress Office of Technology Assessment publication, “[b]y many measures, the Hawaiian Islands represent the worst-case example of the Nation’s NIS [non-indigenous species] problem.” Also, “…Hawaii, the Nation’s so-called extinction capital, has the greatest concentration of threatened and endangered species in the United States…. …NIS have been identified as an important, if not the most important, current threat.” Hawaii, according to the OTA report, is “especially vulnerable to ecological invasions” because of the uniqueness of island ecology; its tropical climate; and the fact that it an international transportation hub.
To read the article entirely please click HERE
This excerpt from the Hawaiian Ecosystems at Risk (HEAR) project website nicely summarizes the invasive nature of the Casuarina:
Casuarina equisetifolia is one of the most “highly invasive, extremely problematic weeds in Hawaii. This species should not be planted anywhere in the state of Hawaii… because the damage that it causes (e.g. to native ecosystems) is permanent and irreversible. It is impossible to have just a few of these plants: Planting just one has effects outside the area where it’s planted; it’s not just the immediate vicinity that can be permanently negatively affected. Nor is it the immediate future that is the only consideration: a planting of a reproducing, wide-spreading species [such as this] can potentially last forever, affecting areas both near and far over time.”
To read what the Hawaiian Ecosystems at Risk (HEAR) has to say about Casuarina trees click HERE
The following excerpt is from an article recently published on June 7th 2011 by The Royal Gazette Online, Bermuda’s most trusted source for news and information, www.royalgazette.com.
When 95 percent of Bermuda’s cedar forest succumbed to the great scale epidemic in the 1950s, the introduced casuarina was perceived to be the ideal quick fix for re-foresting Bermuda because of its rapid growth, salt spray resistance and evergreen foliage. Moreover, it does not readily self-seed in Bermuda soil so nobody expected it to become invasive.
(photo taken on Providenciales, T.C.I)
The first sign that it might become a problem was when we discovered just how incredibly tall they grow in comparison with our native trees. This, combined with their relatively sparse and open foliage, not only diminished their value as a windbreak but actually aggravated the problem by causing wind turbulence and mini twisters in their lee during storms.
These tall trees were tested by their first real hurricane event Emily in 1987 and we discovered that they uproot in droves, destroying everything in their path as they fall. Topping off the trees at intervals as they grow can prevent this problem, but it is dangerous work or hugely expensive if professional arborists are hired to do so.
To read the full article click HERE
When looking at the similar situation our neighbors in Bermuda are facing you can easily come across the website created by the Bermudian Ministry of Public Works and it’s Department of Conservation.
The following is an excerpt taken from a recent article regarding the affects of the Casuarina on the natural Bermudian environment:
“The Casuarina grows quickly and achieves substantial heights, even in poor soil and when exposed to salt spray. These characteristics made it an ideal choice to reforest Bermuda after the cedar blight, but also led to its aggressive invasion of Bermuda’s coasts.
These traits also make Casuarinas likely to blow down in hurricanes, which leads to property damage from falling trees, and coastal erosion as plugs of rock and soil are ripped up by the roots of the falling tree”.
(Photo of ‘Daniel’s Head’ in Bermuda)
To read the article in full please click HERE
Below is an quick summary of what happened in the Florida Keys. This is a perfect example for us here in the Turks and Caicos Islands since we share many geographic, demographic and economic similarities with the Florida Keys.
The section below was taken from The Global Invasive Species Team website.
Non-native species invader : The Casuarina
Already heavily damaged by development, the Keys now face a new threat to their rich native biodiversity: invasion by non-native species. Introduced intentionally or accidentally by humans, invasive species can spread into natural areas, and once established, they can grow and reproduce so rapidly that they outcompete, damage and displace the native plants. The animals that depend upon the native plants suffer next. If left unchecked, these invaders could transform the vibrant, biologically diverse native forests into a woodland of non-native trees that provide little native food or habitat for native birds, mammals, or insects.A Success Story
Alarmed by the increasing infestations of invasive non-native plants, a broad-based coalition of groups representing environmentalists, utilities, municipalities, and county, state, and federal departments formed the “Florida Keys Invasive Exotic Task Force.” Their goal was to eliminate invasive non-native plants from the Keys, and to keep them out in the future.First, they started by mapping the vegetation of the Florida Keys using GIS technology. Specifically, they were looking for invasive species infestations. Once this map was created, they began strategizing and prioritizing their next steps. They produced an educational brochure (Keys’ Invasive Exotic Removal Guide) that was distributed to thousands of property owners.
Next, they identified West Summerland Key as a site for a demonstration project. This 50-acre Key was heavily infested with Brazilian pepper, Australian pine, seaside mahoe, and lead tree. Using labor contributed by Girl Scouts, Boy Scouts, AmeriCorps, Alternative Spring Breakers, and local residents (780 volunteers in all!), the Task Force started removing the invasive species. It took nearly three years and $40,000 in grants and in-kind services (tree felling, brush chipping, etc.) from Task Force partners, but now West Summerland Key is 99% free of non-native species. Where the invasive species were removed, more than 1,000 native plants were planted.
The above success story is a perfect example of the work and efforts it takes to keep an invasive species from damaging new environments. Here in the Turks and Caicos our work is cut-out for us, but it will take many hands, minds and efforts from the local population to help bring our environment back from to the forefront of concern.
