June 8

It’s the 25th day of the trip and the end is getting near, but everyone was still very excited about being in Australia and getting to explore various fragmented Mabi rainforests. We woke up this morning in the wonderful On the Wallaby Lodge and had an unusually relaxing breakfast at around 8 in the morning. During the meal students were able to sign up to purchase didgeridoos and boomerangs from the Aboriginal family we met yesterday, and Ben and Alex had time to fit in a quick game of chess. 

Our extremely knowledgeable tour guide Paul, started his tour of the Atherton Tablelands by taking us to see Cathedral Fig Tree which is one of the largest trees in north Queensland with roots that drop approximately 49 feet to the ground. Cathedral Fig Tree is a massive strangler fig tree whose presence is characteristic of Mabi rainforests. Strangler figs grow when a bird deposits a seed on a host tree’s branch. This seed develops gradually, attaching itself to the host tree and using this tree as a guide for its root system. As the name implies, in time the strangler fig overtakes the host tree and kills it. This strangler and the remains of the host tree function as shelter to birds, snakes and many other animals in the rainforest. 

We next visited Lake Barrine in Crater Lakes National Park. The lake was created nearly 10,000 years ago when a shift in the earth’s climate caused a violent volcanic explosion in the area. The volcano erupted and then caved back in on itself, creating the large crater which we now know as Lake Barrine. Paul explained that relatively no algae grow in Lake Barrine because the surrounding trees’ roots extend into the lake and draw the essential nutrients for algae from the lake. Because of the abundance of water, buttress root systems are common for trees around the lake, as is having less dense timber which can allow oxygen to pass into the root system. The lake has no streams or rivers moving in or out of it and is completely surrounded by Mabi rainforest. 

As Paul led us into the rainforest surrounding Lake Barrine, he explained the strong relationship between the Mabi rainforests on the tablelands and the Great Barrier Reef. The reef emits a gas which helps produce rain clouds to shade the reef from the sun. As these rain clouds move inland they release essential moisture into the rainforest. The rich nutrients in rainforest’s soil get flushed out to the surrounding rivers and streams during such raining periods. Animals feed on these nutrients, and as they flow through brackish water, mangroves filter the water and break it down into organic matter which can be easily used by plant and animal life at the reef. In this way the health of the reef impacts the health of the rainforest and vice versa. 

While in the rainforest, we encountered a black bean tree, which produces a seed that though poisonous to consume, is being used in modern medicine to slow the effects of HIV. According to Paul, research about the various characteristics of rainforest plants is still underway and in the next 20 years or so many more discoveries about how to utilize them properly will be made. 

Upon seeing a fallen tree, Paul explained that when trees fall in the rainforest, sunlight is able to penetrate the canopy and hit the forest floor, which throws off the temperature of the area and provides a window of opportunity for new plant life. First, the faster growing, sunlight-thriving plants like wait-a-while, elephant ear palm, and stinging tree begin to fill the void, creating a low canopy which begins correcting the temperature. Ten years later, a second generation of trees about 5 to 15 meters high dominate the area and start to fill in the canopy. Ten years after that, the trees from the second generation have usually grown to a significant height where they can successfully block out the sun and readjust the heat in that area of the rainforest. I found it particularly interesting that in Mabi rainforests less than 5% of sunlight typically penetrates the canopy and reaches the rainforest floor, keeping their temperature rather cool. On our walk through the forest, Paul warned the group not to brush up against a stinging tree, whose hairs can release a toxin into the skin and cause an intense “stinging” pain for up to a month. He also pointed out wait-a-while, which is a fast growing plant that works like ratchet, connecting the rainforest by grabbing on to neighboring trees and expanding with them as they grow. As wait-a-while vines grow they turn into wicker, which is commonly used to make furniture amongst other things. 

After a quick bite to eat by Lake Eacham, some of the guys and I took the opportunity to go for a quick swim in the lake before we took off to a rainforest corridor with a dedicated ally of the rainforest, Jack Grant. 

According to Jack, the main objective of the rainforest corridor project is to increase plant and animal biodiversity and movement by building corridors which connect fragmented pieces of rainforest. Building a rainforest corridor can be a long, expensive, and labor intensive process and the one we visited heavily relies on volunteers to help build it. We were more than happy to be able to get our hands dirty once again and help stimulate the growth of a rainforest corridor by pulling weeds and help generate an environment in which native plant and animal species can thrive. The weeds in the corridor need to be handpicked because herbicides would not only kill the weeds but could also do damage to the native plants whose growth is essential to building the corridor. 

Jack Grant and other volunteers have planted over a hundred different plant species in the corridor that we visited in hopes that it will help start an intensive regeneration in the area. Bird and reptile species have been moving into the corridor which is a good sign that the corridor project is starting to work. Jack explained that the corridor benefits the farmers who donated the land used in the project, because the trees they plant in the corridor create a wind break for their soil, protect the nearby creek from erosion, and provide shade and shelter for their cattle. The symbiotic relationship between farmers and the environment helps to stimulate biodiversity in the area and is a good example of how environmentally sustainable practices can also be economically sustainable. 

We then went to another piece of fragmented Mabi rainforest with Jack where he pointed out characteristics of various plant and animal life around us and briefly explained the criteria on which rainforests are categorized. A Mabi rainforest (Mabi being the aboriginal word for tree kangaroos) is categorized by its fertile volcanic basalt soil, tree kangaroo inhabitation, abundance of strangler fig trees, the amount of sunlight that hits the forest floor, and the presence of other plant and animal life that are unique to it. The Mabi rainforests we visited were complex (dense) highland tropical mesophil (meaning large leaf) forests. These forests used to be heavily logged for their valuable red cedar timber (going for as much has $40,000 per tree) but are now being conserved for both environmental and aesthetic reasons. Jack discussed with us the current situation that Australian logging is in and told us that though they may have stopped cutting down trees in the rainforest here, Australia currently imports large amounts of wood from countries with histories of illegal and unsustainable logging practices. He emphasized the importance of looking at sustainability on a more global scale. 

After walking through the rainforest we drove with Jack to a gorgeous lookout area where he discussed the history of land clearing and farming in the area. It was shocking to learn that the water used by the farms we were looking at ran off unfiltered, directly into neighboring rivers and eventually into the Coral Sea where any harmful chemicals could easily harm marine life. Though there are some government regulations on the farmers who run the land, much of the responsibility of keeping this runoff water free of harmful chemicals lies on their shoulders. 

Upon returning to the lodge, a few members from the group decided to do an optional platypus spotting walk with Ray, another tour guide from On the Wallaby. The platypus spotting walk lived up to its prestigious 98% success rate as the students were able to spot a platypus swimming across the water just a few minutes into the walk. After the platypus spotting, Paul and the On the Wallaby staff cooked a delicious spaghetti dinner for the group. The night ended with an amazing wildlife spotting canoe trip. Because of the limited amount of light pollution in the tablelands, the night sky was clearduring two-hour canoe trip.  On the trip, students spotted a large iguana, wallabies, and a few even got to see a tree kangaroo. All in all, it was one of the most hands-on and exciting days we’ve had in Australia so far. 

To learn more about where we stayed be sure to visit the On the Wallaby website at: 

http://www.onthewallaby.com/index.html 

I found the videos on the website to be very informative and relatively entertaining. 

If you are interested in Mabi rainforests this link provides a very good background: 

http://www.treat.net.au/mabi/mabi_more.html 

Jack Grant talking to us about farming practices in the Atherton Tablelands at the lookout.

 

A lizard we found when picking weeds.

 

Sean, Anna and Jenna picking weeds in the rainforest corridor.

 

Stinging Tree (Aboriginals referred to it as Gimpy Gimpy)

 

Curtain Fig Tree

 

Paul showing students a wait-a-while plant.

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: