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koala research

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Koala Headlines

“Koalas no more in our bush”
“Koala listing another example of government ‘greentape’…”
“Koala listing offers no protection from logging”
“The vulnerable koala: are we in time to save our national icon?”
“Koalas get some protection in parts of Australia”

These are just some of the headlines coming out of Australia these days. And for good reason: Environment Minister Tony Burke announced on April 30 that the federal government decided to list the koala as vulnerable in New South Wales, Queensland, and Australian Capital Territory. However, there are two other states that are part of the koalas’ home range, Victoria and South Australia, where the federal government did not list the koalas as vulnerable, and this is bringing up some debate and discussion.

While is it is great to see the conservation research of Bill Ellis (former San Diego Zoo Institute for Conservation Research postdoctoral fellow and still a research collaborator of mine) being used in the political arena by helping the federal government come up with the vulnerable determination for koalas, there is always more that could be done. The debate and reason for the lack of protection for southern (Victorian) koalas is that there is a common misconception of the robustness of the southern ranging koala population, since there are high numbers in that region.

More than population numbers need to be taken into account when listing an animal. Kellie Leigh, conservation biologist from the Australian Ecosystems Foundation (and a collaborator with me on koala scent studies), says many of the large koala populations in Victoria have been bred from a small number of individuals that were reintroduced from the French and Phillip islands. “There is evidence that these populations suffer from inbreeding depression, including things like testicular abnormalities,” Dr. Leigh says. “This lack of genetic fitness also means that the populations are much more susceptible to pressures like disease.”

The idea that the Victorian koalas are “eating themselves out of house and home” perpetuates the idea that this population of koalas does not need protection like their northern counterparts. “Looking at numbers alone is just not meaningful in conservation terms. While the listing is welcome and a step in the right direction, we need to conserve the koala right across the species range if we want to hang on to this iconic animal,” says Dr. Leigh. Even with scientific input on the declining numbers of koalas in the northern states, the koala was not listed to the highest level: endangered.

It is wonderful that the San Diego Zoo has a robust colony of Queensland koalas for all Zoo visitors to see. And we will soon have a new home for them, opening in Spring 2013. But in my 10 years of koala research, I didn’t think that there might be a time when I might not see a koala in the wild. As a guest at one of my first talks at the Zoo asked, “Why are you studying koalas if they are not endangered?” My response was that their foothold in Australia could change at any time and could cross that threshold. Unfortunately, I am sorry to say that this is where we are heading. However, all is not lost, and the crusade for preserving the koala in Australia is strong. Although this listing does not cover all the koala populations, it is one more step in the right direction. So the next time you stop in and see our koalas, remember their wild counterparts and that there is reason for hope!

Jennifer Tobey is a research coordinator at the San Diego Zoo Institute for Conservation Research. Read her previous post, Victorians: The Other Koalas.

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Koalas and Cyclone Ului

Wow! I have now finished my surveys of koalas on all the islands and mainland near Mackay in the state of Queensland, Australia, and can report that the damage done by Cyclone Ului back in March 2010 was quite impressive. The week on Rabbit Island and the adjacent mainland last month was a real eye-opener for me. I have been studying koalas in the relatively benign environment of St. Bees Island for over 10 years and the nearby islands for 4 years. In that time I have not seen any cyclones hit the islands this hard, so I had no idea of the kind of damage these storms are capable of.

Cyclone Ului hit Rabbit Island very hard, and many of the koala-food trees were denuded of the leaves koalas rely on. As we searched that island, we were continually stepping over fallen trees, often large eucalypts that would have been a comfortable resting spot for a koala before the storm.

The picture was the same on the mainland, with large blue gums having been reduced to high stumps, their tops torn off by the storm. St. Bees Island was hit in a strange way: in some areas there was little damage, but in other places whole trees were uprooted or simply snapped off. One would imagine it must have been a frightening time for the koalas, with tree branches flung around, and no doubt some of the koalas probably perished in the storm. What I found most interesting was that while the blue gums (the favorite food of koalas on St. Bees) were often broken by the storm, these trees retained many leaves. In comparison, the ironbarks (also eaten but less preferred) tended not to lose branches but did lose all their leaves.

Unfortunately, fallen trees or large branches now mostly cover my usual tracks around St. Bees Island, so when the other researchers from the San Diego Zoo come out in September and October, we will be taking different routes. There is so much fallen timber on the ground that my concern now is that if a fire was to strike the island, there is so much fuel that it would be very hot and dangerous for koalas.

The good news is that I found five new koalas in our main study site (“the knoll”) on St. Bees Island, all very healthy and enjoying the cool breezes that we get at this time of year. I also found Elizabeth, one of the grand old ladies of our research; she has been on the knoll since 2000, so she is getting quite old but is still in good health and bringing up a young koala each year (see Urban Koalas). We also renovated all the listening stations, and we deployed three new stations to record koala bellowing on St. Bees Island when the breeding season gets underway. In October some of the team from San Diego will be here researching the koalas’ bellows, so I have been busy getting the recording boxes deployed and mounting new solar panels in anticipation.

Fortunately, none of our radio-collared koalas died in the cyclone, which makes me think that maybe these animals are better at surviving the wilds of the weather than we might think. I would love to know what they do when the wind gets so strong that it snaps branches and whole trees. There is still much to learn about koalas.

Bill Ellis is the Clarke Endowed Postdoctoral Fellow with the San Diego Zoo Institute for Conservation Research. Read his previous post, Covering the Land, Koala-wise.

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Covering the Land, Koala-wise

Volunteer Gabriella with one of the koalas in the study.

The weather has turned cool, but the strong winds that accompanied cyclone Ului are long gone, and once again we are in coastal Queensland, Australia, looking for koalas (see previous post, Koalas: Not All Doom and Gloom). We have spent the last week in the west, catching koalas at Clermont, but now we have the sea to look at instead of the open plains. Our project at St. Bees has uncovered many interesting facets of koalas’ lives, but sometimes the most interesting things come to you by chance, and this trip is the result of one such chance.

The koalas of St. Bees Island were introduced way back in the 1920s and 1930s and occur in a relatively stable population of between 200 and 300 individuals there. We have been investigating their genetics to understand how their breeding system works. We want to know which males do most of the breeding, why some males might miss out, and what sort of strategies different koalas adopt to keep them in the race to reproduce. Along the way, we have had the opportunity to visit other islands near Mackay that are also inhabited by koalas, and we have collected genetic material from these koalas.

Local anecdotes tell us that the koalas on Brampton, Rabbit, and Newry islands are the decedents of the koalas on St. Bees Island, moved by various people over time, but our genetic data, collected by chance, tell a different story. On this trip, I am looking at the koalas on Rabbit Island (close to the coast) and also looking around the local mainland area to try to find koalas. These mainland koalas may be the key to this story, because if they are closely related to the Rabbit Island koalas, then this will suggest that the koalas on Rabbit Island are another natural island population, making them very important to the conservation managers in Queensland. It may be that koalas have made their own way to Rabbit Island, either by swimming the channel to the island or maybe using a previous land bridge many, many years ago.

We are based in Seaforth for this trip, a lovely seaside town north of Mackay and close to the islands. I have a great team of volunteers and colleagues scouring the bush by day, and we are again being helped by the Queensland National Parks rangers, who are taking us by boat to the island when we are not looking on the mainland.

We have caught six koalas on Rabbit and Newry islands so far, but found none on the adjacent mainland yet this trip. I really hope we can find enough koalas left on the mainland to resolve the issue of where the koalas on Rabbit Island came from. To do so will give the National Parks a powerful tool to ask for more resources to manage the islands against pests and fire.

For us, it will be rewarding to provide some positive input to the management of koalas. For the koalas of Rabbit and Newry islands, it could well determine their future, as well as their past.

Bill Ellis is a Clarke Endowed Postdoctoral Fellow for the San Diego Zoo’s Institute for Conservation Research.

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Island Koalas: Meet Orbit

Little Orbit meets his admirers.

Little Orbit meets his admirers.

Greetings again from St. Bees Island! We have some great news. Some time ago I reported that Elizabeth, the female koala we have been tracking for the longest time, had a baby in her pouch (see Island Koalas: A New Season). I have been very keen to find her again and see whether I could examine her baby before it left her for good. I am happy to announce that we have a new member of the koala group on “The Knoll,” and his name is Orbit!

We were heading up to the very top of the knoll, where Elizabeth can usually be found, tracking her radio signal when one of the volunteers shouted, “I can see one.” There was a pause and then “She has a baby on her back.” I was excited, because I was hoping to find Elizabeth healthy and with her young, and there she was, in a 33-foot (10-meter) blue gum, looking down at us…with a small furry face peering over her shoulder as well.

We were able to encourage her down the tree using our usual flag-waving technique; we simply wave rags and plastic bags (attached to long poles) above the koala’s head while remaining very quiet below. Distracted (and probably annoyed), the koala descends the tree and we grab it when it is low enough. On this occasion we got two for one, with the little koala attaching himself to one of the volunteer’s legs (fortunately long pants were worn) when we placed Mum in a bag.

Elizabeth has put on weight since her last capture, which is interesting, considering she has to carry the extra weight of a young koala around all day and night. She was in very good condition, which is great news since she is over nine years old. Orbit (her baby) weighs about 28 ounces (800 grams) right now and will probably stay with her for a few more months. Elizabeth has had mostly male babies, and this was another one.

We replaced Elizabeth’s VHF collar with one of the GPS collars we received through the San Diego Zoo’s Ocelots program funding, so now we will be able to monitor her movement every four hours for the next five months, even when we are not at St. Bees. During this trip we’ve deployed ten such collars, six on females and four on males.

After examining Elizabeth and Orbit, we set them free and they climbed back up the tree to resume resting and eating, with Orbit clinging on to his Mum’s back. It was a great day for us, but I guess the little koala is wondering what it was all about.

Bill Ellis is a Clark Endowed Postdoctoral Research Fellow for the San Diego Zoo’s Institute for Conservation Research.

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Koalas: Floating Research Station

It has been a busy month for the St. Bees Island koala project, not that you would know it from the number of koala bellows we are recording on the island. (See previous blog, Koalas of St. Bees Use Cell Phones.) As usual, when the koalas over at the San Diego Zoo are getting their vocal chords warmed up, those at St. Bees are being quiet. I have just stepped off a boat that has been my home for the last few weeks, having finished a survey of the other islands that lie close to St. Bees, off the coast of Queensland, Australia.

Thanks to our close relationship with the Queensland Parks and Wildlife Service (QPWS) rangers, I was fortunate enough to travel aboard the Tamoya, a 43-foot (13-meter) catamaran that is operated by the Mackay Marine Parks team to conduct their island infrastructure maintenance and compliance work. This boat became our home as we stopped in at a few of the other islands that are home to koalas in the Whitsunday region of Australia.

First stop was Newry Island, then Rabbit Island, then across to Brampton, and finally, St. Bees. Newry and Rabbit Islands are very close to the mainland and we suspected that koalas from these islands got across the mudflats to visit their coastal counterparts. To check on this, we put a Global Positioning System collar on the only koala (named Nigel) we found on Newry Island last year. We found him on the current trip and downloaded his GPS data. Nigel never left Newry Island, although his GPS data revealed that he had traversed the whole island while we were away. I wonder how he got to the island, if he doesn’t ever leave?

After finding five more koalas on these close islands, we floated off to Brampton, where we found more koalas, even a small koala (named Inky) that Fred Bercovitch and I had found in October last year. It seems that this population of koalas is larger than anyone had predicted. The koalas on Brampton Island are also quite healthy, and judging by the number of young koalas we are finding, they aren’t having any problems finding one another in the rain forests.

Finally, to St. Bees, where we renewed acquaintances with all the regulars. Koala Elizabeth was looking very well and has a two-month-old pouch young, so she bred later than usual this year. I even found The Hurricane, a big male who has evaded us since he broke his collar two years ago. I hope to bring him back into the “collared crew” on a later trip this year.

I was very lucky to be able to travel with the QPWS crew for this trip, but we are already planning for another trip with the rangers in the future. Since part of their job is looking after all the wildlife on all of the islands, they too are interested in the koalas of St. Bees.

Bill Ellis is a Conservation Research postdoctoral fellow for the San Diego Zoo.

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Koalas of St. Bees Use Cell Phones

Hello again from St. Bees Island, off the coast of Australia, where it seems the koalas have taken a break from their nightly ritual of bellowing. Not many people actually get to hear a koala bellow in the wild, but our San Diego Zoo Conservation Research team has found a way to do it all day, every day. Actually, koalas call mostly at night, but just in case, we have been listening in 24/7. We have been using mobile phone technology to listen and transmit the sounds from St. Bees to our computers, with some interesting results.

We have a male koala bellow for you to listen to:

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This project began in earnest at the start of the breeding season on St. Bees Island, which is at the start of September. We are very interested to know what is the purpose of the bellows male koalas make during breeding times. It could be a cue for other males to stay away or may be some form of advertising for females, but it turns out that, like a lot of aspects of koala biology, there is plenty to learn about this behavior.

We have placed three solar-powered remote listening stations on St. Bees Island. These microphones record sound onto a mobile smart phone for two minutes, every half hour, throughout the day and night. Once recorded, the sound is transmitted directly to a server in Brisbane and uploaded onto a Web site, managed by our partner in this project, Queensland University of Technology. We can usually analyze each recording within 10 minutes of it being captured, so we have some very up-to-date information on what is going on at St. Bees, even when we are not there.

So far we have found that koalas do indeed do most of their bellowing at night; bellows during the day are very uncommon. We have found that the average length of a call is around 40 seconds, with some lasting up to nearly 2 minutes. Although at first we found more calls occurring around midnight, as the season has progressed this trend has been less apparent, and it seems that the calls change in structure as the season progresses.
We have also been fortunate enough to capture some interactions between males and females, where we have heard both animals vocalizing while they are interacting.

What we will be doing in the coming weeks is downloading the GPS data from all of the radio collars worn by the koalas. This way we will know whether males, or females, move more when we hear the most calls. This should indicate whether males are talking to other males or to females.

Since Christmas, there has been a marked decline in the number of bellows we have heard on the island. This is interesting, because although we know the bellowing is a seasonal phenomenon, no one really is sure what triggers the start or end of it, or how important it is to breeding for koalas. These are the sorts of questions we are trying to answer through our research at St. Bees Island.

We expect that fewer and fewer bellows will be heard as the koala breeding season in Australia comes to an end during March. Fortunately for visitors to the San Diego Zoo, this signals the start of the Northern Hemisphere breeding season, so although there might be few calls from St. Bees, there are likely to be plenty coming from the koalas at San Diego!

Bill Ellis is a Conservation Research postdoctoral fellow for the San Diego Zoo.

Read Bill’s previous blog, Koala Tracking with GPS.