On the brink

We are 'on the brink' in many ways.  The field season is almost upon us, and a lot is about to happen at Cape Otway.  It is definitely time for a blog update.

Our koalas
In May, I captured 15 koalas wearing VHF collars, for health checks and to attach new GPS devices to their collars.  Thanks to some wonderful volunteers (Samantha, Teagan and Lisa), we accomplished this in just two days, and also managed to plant some trees too.  We had to be extra careful and gentle with the girls because most of them had large pouch young.  Claire's joey, one of the first to be born this season, was actually out of the pouch (but hid inside during the catch).

Claire and joey, May 2013

Our catch list was:
Females: Lucie, Claire, Ruby, Buffy, Nelly, Sally, Lison, Bella, Elena (Katrina's dropped her collar).
Males: Ned, Beast, Austin, Stevie, Scarface, and of course, Cranky Frankie (Tony Parker is MIA... AGAIN!)

Bilko, Erik, Al, Dave and Mac were wearing the GPS collars so didn't need to be caught, although we did track them.  Sadly, we found Mac dead.  A week earlier, a small control burn was put through part of the site to help regenerate the Manna Gum.  Mac must have been in the wrong place at the wrong time. 

Since May, Bilko has also departed us.  He was one of my first koalas to be caught at Cape Otway (in 2010), and was looking good in May.  I can only guess that age and his difficulty in obtaining good nutrition caught up with him.  I retrieved and cleaned off his skull - I have never seen such an odd-shaped skull or such a poorly aligned jaw in a koala.  I'm surprised he was able to eat at all.

Bilko's mishappen skull

Bilko in May 2013 - happily feeding


Our trees
On a very sad note, trees at Cape Otway have taken a rapid change for the worse.  The green flush of growth from December - March provided a bit of hope, but with the trees entering a dormant phase over winter, koalas have stripped many of them bare.  Some trees in our site have died and many are barely hanging on.  The koalas have shifted their ranges slightly as a result.  Most of them are sitting in trees that still have some leaf, along the fenceline, while others have moved out into the paddock trees.

Trees in our site take a turn for the worse

BUT THERE IS ALWAYS HOPE.....

The trees we planted (germinated from seed collected by Earthwatchers in April 2012), are looking good, and there are young seedlings emerging in the burnt areas.  I have already started germinating seed (collected by Earthwatchers in February 2013) for trees that can be planted in Autumn 2014.



Mannas are germinating in areas burnt in May

Manna from seed collected in 2012



Plans for the 2013/2014 field season
A focus of our work this summer will be assessing habitats (tree condition, regrowth, etc), and taking action to ensure that our new trees (planted and naturally germinated) have the best chance of survival.

Koala censuses and tree condition assessments will be conducted in all of our sites across Cape Otway (Aire River, Lighthouse, Parker Hill, Bimbi and Bimbi West).

We'll also be doing some behavioural studies to further our understanding of mate selection.  I will be replacing VHF radiocollars with VHF/proximity collars which will record who is near who, and the length of time they stay together.  We suspect that males guard females until the females are in oestrus and receptive, so this will provide detailed and continuous information on that throughout the breeding season.  I will also be deploying some accelerometers for analysis of the frequency of an individual male's bellows during the peak breeding period.  This will provide insight into testosterone cycling as well as mate selection (are females really attracted to the males that bellow the most?).  Some of the catching for these studies will occur during the November Earthwatch trip.

Dave likes to bellow when I'm around

Radiotracking will occur in all trips and help us understand the daily movements of koalas and tree selection, especially with respect to the changes in tree condition.

Scat collection will also feature as an activity.  The nutritional value of koala food can be determined from scat.  We will therefore be able to see if there is a relationship between tree cover decline and koala nutrition.

We will continue with camera trapping in February.  Koalas aren't the only ones using manna gum woodland.  This will tell us what other species are also present, and how they are being affected by the changes in habitat.

So, lots to do, and exciting times ahead.  Alistair will be leading the September trip and I will be leading the November and February ones.  For those of you who will be joining us, THANK YOU in advance.  I hope you have a fun and rewarding experience with us.


AND FINALLY....

If you didn't catch it, ABC Catalyst did an episode on us.  Check it out at ABC Catalyst - Cape Otway koalas and Deakin/Earthwatch research program

And, the study on koala bellows conducted at Cape Otway (lead by Ben Charlton), is now in press and can be accessed at: Koala bellows (Charlton, Whisson and Reby 2013)










Is 6 a lucky number?

If not, it should be.  This was my 6^th Earthwatch trip, there were 6 participants, and we had at least 6 days of sunshine and days of making good memories.  We may have had more of the latter but I want to go with this theme of ‘6’.  Oddly enough, the number ‘6’ featured in Frankie’s, or should I say “Cranky Frankie’s” collar frequency, so maybe the number ‘6’ isn’t so lucky afterall.  Frankie will go down in history as the most terrifyingly aggressive koala to ever grace the trees of Cape Otway.  I have never known a koala to feel such a need to attack his catchers… and this time, we had to catch him not once, but twice!

"Cranky Frankie" - don't be fooled by this photo. He has a nasty streak a mile wide!

 

But, I digress….

To my February band of koala-ers: Anndy, Krystal, Kelly, Tim, John and Robert, and staff Viki and Jo, a huge THANK YOU for your hard work, good company, and pulling me out of the field trip doldrums I was feeling at the beginning of the trip.  I had already spent so many weeks in the field prior to this trip that I was tired and feeling a little grumpy.  You guys soon turned that around though.  I can’t believe I even laughed while battling the prickles and general nastiness of Aire River?!  The food was also sensational.  My favourite was the Mexican fajitas, although the risotto was a close second.  Nothing like a hot fudge brownie or apple crumble with vanilla ice cream to finish off a meal either.  I will have to post some of these recipes in a blog to follow this one.

The amazing February 2013 team including Jessie and Kara

We accomplished so much too:

1.       Census at the Bimbi site
Sadly, we are now at around 22 koalas per hectare.  It appears that many of them are youngsters that have just been weaned.  Those ones seem to be having a difficult time finding a place in the already crowded trees.  During the week, we came across some that were very weak, and others that were turning to humans for comfort.  The little female I moved off Manna Gum Drive twice(!) pulled at my heart strings.  It is frustrating to observe this population increase and not to be able to do anything about it.  Culling to reduce the population is out of the question (banned at the Commonwealth level), translocation has its own negatives in terms of animal welfare, sterilisation will not work quickly, and habitat works are also long-term options. It appears that nature will have to sort it out but in the words of a former colleague “Nature…. She’s a cruel bitch”.

2.       Radiotracking



Trying to find Frankie



Each day my band of warriors headed out, armed with receiver and antenna to find our koalas.  Sometimes, I think these koalas like to play tricks on us and switch places to see if we’re paying attention.  Dave headed out to Katrina’s tree, and Mac and Austin traded places a few times.  Cranky Frankie simply headed into the thick scrub of the National Park where he hid in Casuarinas.  Wally remained in the same tree but his arm looks to be mending which made us all happy.

Wally - often in the strangest of positions

3.       Tree canopy assessments at Bimbi and Aire



Nothing like a mum and joey to distract
from doing tree assessments



We managed to find and assess most of the permanently marked trees at both sites.  There were a few distractions that slowed us down: at Bimbi, Krystal, Anndy and I got distracted by a mother and her joey who were creating beautiful photo opportunities for us.  At Aire River, prickly vegetation and the difficult terrain made it hard.  Krystal – I can’t believe you kept smiling that day, and then volunteered for finding Stevie, playbacks, AND spotlighting afterwards. Superwoman!



4.       Spotlighting
Three sites were surveyed, the most interesting being Aire River.  We saw koalas, ringtail and brushtail possums, boobooks, tawny frogmouths, bats and a hotly discussed sleeping ‘red wattle bird’.  The moon was sensational too!

What is that you see Tim? Odd how those spotlights look like bananas.

5.       Camera traps


What does this fox have in its mouth?

Our 20 traps captured some great photos of wallabies, possums, koalas, rats (all black rats!), an echidna, a fox with something in its mouth (sorry guys – I don’t think it was a rabbit afterall), lots of birds, a skink (no snakes!), and a horse.  Despite the quantity of photos, there was little diversity. 

Unfortunately, these woodlands are quite disturbed and offer poor quality habitat to most small mammals.






6.       Seed collection
An amazing amount of seed was collected (under the supervision of the horses).  I have it drying in a big tub at home and will start sifting it soon.  Frank and Katrina (owners of Bimbi Park) have given me loads of seedling containers and I plan on building a greenhouse so that I can get some new trees going in early spring.  In the meantime, I have some trees ready to plant from seed germinated last year and Frank has a lot he purchased so I plan on heading down in April for a planting weekend. Let me know if you want (and are able) to join us.

7.       Bellows
Three males caught (including Frankie) but only Beast gave us any bellows. BUT, I am pleased to report that those 2 bellows have given me a data signature on the accelerometers. I’m now working out how to search for that pattern in accelerometer data collected in the last couple of years. I also have found a student who wants to look at this for his honours’ project. It will be interesting to investigate the link between bellowing and reproductive behaviour.  

Each coloured line represents an axis of the accelerometer.  Beast gave two short bellows in succession.  The movement of his head up and down resulted in a regular pattern on two of the axes.

 

Tim with Dave

8.       Koala catching
Because most of the koalas had been caught in January, we only needed to catch the three boys for bellows and Lucie, Katrina (and joey ‘Manya’), Sally, and Buffy for gps switch.  Lucie was the sweetest of all (as always), but it was Katrina who got to be the film star again.  This time it was a German film crew.  They seemed to realise that we could only do the capture once, but I lost count of the number of retakes they did of me walking to the car, putting poles in, taking poles out etc.

9.       Leaf sampling
Kara and Jessie joined us for most of the trip to do some leaf sampling for a project on leaf chemistry of trees throughout the national range of koalas.  So, we got to help collect some leaves for them.  Tim deserves a special thank you for spending 3 days collecting leaves.  He tells me that shooting the ‘Big Shot’ slingshot in the blue gums made it worthwhile J

 

And I think that just about wraps it up for February.  Did I miss anything? I suspect so but this seems like such a long list of accomplishments already, and I don’t want to scare off future volunteers.  They already have a hard act to follow.

Nothing like an amazing sunset to top off a hard work day!

 

 

RIP Kevin

Kevin - in better times

I have been meaning to post this for some time.  In mid-January I was sad to find the remains of Kevin.  I had not predicted his death. We attempted to catch him in December for a health check but he simply glared at me from his distant perch (barely within my reach) in a dead limb and refused to be persuaded down.  He always seemed to be in the thick of any action at the site so I’m guessing he simply wore himself out.  I will miss you my grumpy, stubborn friend.

The exciting news though is that In January, Ruby had a jellybean joey in her pouch.  By its size, I reckon it might just be Kevin’s.

Wally is also still with us.  He is now in a tree near the gate from the paddock into the site.  As much as I would like to get the accelerometer and GPS off his collar, we won't be catching him until he's in a much improved state.

'Beast' to be a movie star

On the 18th December, Cass, Vic and I headed back down to Cape Otway for some catching and to meet with a film crew from ABC Catalyst.  The crew had been on the road since early November, travelling from Perth to Melbourne to collect as much material as they could for episodes to be aired in early 2013 (see http://www.abc.net.au/catalyst/stories/3642016.htm).  They wanted to do a story on the overpopulation of koalas at Cape Otway, landholder views, and our research studying the issue.

I think we were all a bit nervous about being in front of the camera, and the fact that they wanted to film us catching a koala didn't help.  As some of you know, koalas aren't always the easiest animals to deal with and I've never been able to predict an 'easy' catch.  At first, I think the reporters wanted to be my catching team but thankfully, I was able to talk them out of that. So, just prior to their arrival, Cass, Vic and I searched for a koala that might be 'easy' to catch.  We really wanted a female to add to our sample of collared koalas.  We found a female with a joey in an isolated tree out in the paddock.  'Beast' was in the same tree and quite low, but given his size and usual mean temper, we decided to leave him alone. 

The crew were happy with our choice of filming location and koala 'talent'.  They loved 'Beast' with his grumpy look and battle-worn face and took loads of footage of him.  As for the catch.... our little mum and joey behaved beautifully. The only thing that would have made the catch more perfect was if they'd walked into the catching bag themselves.  The mum put up a fight once in the bag though which made the noose tricky to remove.  I ended up having to restrain her on the ground to get it off.  The mum was tiny although big enough to collar.  The joey was only about 700g so provided the 'cute' factor.

The crew was a bit disappointed that we wanted to work fast so as to reunite mum and joey, and release them quickly.  But, they were excited with the turning on of a collar (about 5 retakes of that) - there's something exciting about a machine that goes 'bing'; and happy to take footage of us looking into a catch bag and pretending it contained a koala.  After multiple retakes of us watching the koalas back in the tree, and some goofy comments about koala behaviour, rain forced us back to Bimbi Park.  I then was interviewed with my laptop opened so I could look 'scientific'. 

It was a looooooonnng day and we didn't get back to Melbourne until about 10pm.  My fingers are crossed that it comes out OK.  It will air sometime in March.  I'll post a blog when I have the exact details.

Bruce

Bruce

~2003 to December 2012

 

 

Bruce was definitely a favourite and I will miss him.  I'm sure his genes will live on in the Otway koala population though. I'm glad you had such a long life Bruce. RIP.

A legendary effort by legendary people

It is an extreme understatement to say that the November team worked hard.  Our achievements include:

·         Koala census completed at 9 sites (including Aire R)

·         160 randomly selected trees in 8 sites assessed for condition

·         21 new trees tagged and measurements recorded

·         28 tagged trees assessed for condition at Bimbi

·         72 tagged trees located and assessed for condition at Aire R

·         22 koalas captured for health assessment and collar check

·         154 locations of radiocollared koalas recorded

·         4 trees collared

·         Lots of laughs!  

A big THANK YOU to my volunteers: Heather, Leigh, Vicki, Dolores, Helen and Louise; and staff: Cass and Vic for this absolutely amazing effort, and for your never-ending enthusiasm and companionship.

The November team

 

As for our koalas:



Tony Parker - mug shot

Tony Parker lived up to his legendary status.  He dropped his collar on Day 1 of the trip and we didn’t find him until the last day.  He made me climb to catch him and then casually moved into a neighbouring tree just as I got into position.  It was a major effort (for us, not him) to finally get him down the tree. 

 

 

 

Frank is just as feisty as ever and again tried to attack me as soon as he was on the ground.  Dave is doing well and always bellows a greeting and sometimes shows his excitement in ‘other ways’ (use your imagination here). After the excitement of recollaring Banjo in October, he has managed to yet again break his weaklink and is currently MIA.  Claire is also MIA.  Buffy has a joey ‘Willow’ that is extremely cute, and Ruby obviously is ready for another. The whole team was lucky (or perverted?) enough to watch Ruby and Kevin ‘hook up’.  Ruby actually initiated it – Kevin appeared surprised but certainly up to the task.

Ruby’s former joey Benjamin is now apparently independent and perhaps a bit lonely.  He took a liking to Dolores, chased her and started climbing up her leg.  Even after being prised off and released, he still attempted to climb the nearest pair of legs.



Wally

Bruce

Wally and Bruce are my biggest concerns. Wally had a huge abscess on his upper forearm. We didn’t notice it until it burst during handling. It’s typical of a fight wound. He was still able to climb and was observed in the next few days high in the canopy, but he’s lost almost 1kg since we weighed him in October. Bruce is looking battle-weary. No major wounds but his ears are torn and bloody, and he’s lost 1.5kg since October.

The rest are looking good. New recruit Stevie kept us busy guessing where he was going to move to next (he's now down near Lighthouse Rd), and Beast likes the isolated trees between the site and Big Hill.

Stevie

We also have three new koalas: Cyril, Harry and Sally. The two new boys are wearing new GPS collars (thanks to the Foundation for National Parks and Wildlife).


 

Sally and her joey

 

And, as for what it all means….

I'm still wading through all the data but some preliminary analysis tells a pretty grim story for Manna Gum at the Cape.  In April 2011, almost half the trees assessed in the main site (where koalas are being tracked), had a reasonably healthy canopy of >50% cover. Now, less than 5% have >50% cover (Figure 1).

Figure 1. Decline in %trees with >50% canopy cover from April 2011 to November 2012.

If we just look at those trees that we have monitored since April 2011, mean percent. canopy cover has declined from 51% to 33% (Figure 2).

Figure 2. Mean %Canopy Cover of trees monitored since April 2011

This really is no surprise considering that there are around 18 koalas per hectare munching on the trees in the site.

So, what do we do? That is the question that both landholders and the Victorian government is now asking.

Cull? We can’t cull koalas – culling is not permitted under the National Koala Conservation and Management Strategy (and that is not going to change!)

Translocate? It would not be effective to translocate koalas – koalas would just move in from neighbouring areas, and besides, translocation does not always have a happy ending for the translocated animal.

Sterilise? It would not be effective to sterilise koalas – the trees are already struggling and sterilisation takes a long time to act to reduce a population.

Protect and restore habitat? I think this is the only way forward but one that will take a lot of effort and money.  It also won’t ‘solve’ the problem but at least we will save some Manna Gum which can serve as seed trees for future revegetation efforts.

But, what happens to the koalas?  Will they starve as the trees die? Or will they move on in search of better habitat?  I suspect there will be a bit of both.  Some koalas won’t have the energy to move.  They may already be weak from fighting during the breeding season, or may be burdened by joeys.  However, results from our radiotracking show that koalas (both males and females) are able to make long-distance movements.  Some of our koalas have moved several kilometres over a period of days or weeks.  Sometimes, they have spent several days in areas where there are no food trees.  Only time will tell….

 

Cape Otway Koalas in the news

A reporter holidaying at Cape Otway noticed the dead trees and koalas and suggested to his editor that they do a story on the issue.  This article in the Geelong Advertiser resulted in a flurry of interest from radio stations (including national ABC radio) and two TV channels (7 and 9 news).  Frank Fotinas (owner of Bimbi Park) found himself in the limelight and decided to share some of the attention with me.  I was busy for most of the day with radio interviews and 2 TV interviews.  Things quietened down fairly quickly but the media has sparked the interestof the makers of the ABC show 'Catalyst'.  They will be coming to the Cape in December to film our research activities and do a more indepth story on the issue and our research.

The following is just some of the news:
Geelong Advertiser: http://www.geelongadvertiser.com.au/article/2012/10/10/352819_news.html
ABC: http://www.abc.net.au/news/2012-10-10/koalas-destroying-cape-otway-manna-gums/4305628