Nightjars

I've just returned from a wonderful 2-week trip to the Kimberley region in WA's far north. It was just fantastic to get away for a while and as always the scenery is stunningly spectacular!

One of the highlights for me was being able to photograph at close range two of our secretive nocturnal birds: A Spotted Nightjar (of which we saw about 12 in one night driving along a dirt road), and an Australian Owlet-nightjar, of which there was only one!

Here are the best of the bunch - aren't the markings of the Spotted simply amazing!?

Galahs - Changing Places

When Europeans first paddled a long boat up Derbarl Yerrigan (Noongar for the Swan River), Perth was a very different place. The coastal plain was covered in Banksia woodland, and the hills were blanketed in virgin forest of giant jarrah and marri trees. Inland of the Darling Range stretched an enormous woodland of wandoo, weerluk (salmon gum) and other eucalypts. Today this has been replaced by a vast area of agricultural land which is known as the Wheatbelt, but, as a result of salinity and climate change, is fast becoming a barren wasteland.

Felling trees on a landscape scale, replacing them with shallow-rooted cereal crops, spreading many introduced grasses, and installing thousands of bores and dams altered southern inland WA forever. There are still pockets of bushland, but the wildlife these areas (and the broader region) can support is a shadow of its former self. However, not all animals were negatively impacted by land clearing. Some have benefited enormously from the landscape changes, and changes in their population has an affect on Perth bushland. How?

The Galah (Eolophus roseicapillus; also called the ‘pink-and-grey’) once only occurred far inland, more than 500 km to the north and east of Perth. It began to visit this region in the early 1900’s, but only occasionally. When land-clearing went full steam ahead between 1930 and 1960, its population boomed, colonising the south-west in a relatively rapid, widespread expansion. This was a result of a huge increase in its main food (the seeds of grasses, including wheat), and the supply of permanent water on farms. It was not until the 1980’s that this bird established at Armadale. Such information is only available because a few dedicated ornithologists carried out survey expeditions and kept track of changes happening across the state. The information is stored in the WA Museum, highlighting the importance of wildlife study and record-keeping institutions in our society.

 

The extent of galah chewing on this Marri tree is evident

Bleeding and re-sprouting shoots are signs of stress.

 

Galahs are now very common in the south-west, including the Perth suburbs. Like many birds, they breed in tree hollows, being the only cockatoo species to use other material (gum leaves) to build a nest inside. They also happen to be a very aggressive guardian of nest hollows, so once galahs move into a tree, they chase other species away, deterring many smaller birds from breeding. They have even been recorded driving out larger, endangered species like Red-tailed Black Cockatoos.

Their long-term attachment to a nest tree also means galahs like to advertise that ‘this is our place’. To do this they chew huge patches of bark off the trunk, and wipe powder from their feathers onto the bare patch, leaving a chalk-like appearance. It’s thought that ‘painting’ this smooth surface white makes it highly visible to other galahs (and perhaps other parrots), which probably see an extra vivid mark by seeing in the ultra-violet spectrum. The blue patches just below the cheek on male Budgerigars don’t look particularly vivid to us, but to a female budgie, who can see ultra-violet light, they glow very brightly.

 

It has been suggested that this Galah chewing habit aims to stop nest predation by climbing animals such as goannas, which climb trees to raid nests. However, there is no real evidence to support this: no goannas have been known to lose their footing on smooth bark, and the scars are not made right around the tree, just on one face on the same side as the nest entrance. There were also early theories that Galahs aim to kill trees and speed up the hollowing process, thus creating future nest sites, but, as Ian Rowley says in his early publications on Galahs, no animal is known to be capable of such a degree of forward thinking.

Whichever the case, Galahs have become so common in a region where they previously didn’t occur, and this isn’t a good thing. In many patches of bush around Perth, all the large, hollow-bearing trees have a resident pair, defending their home from most other birds and giving them ‘Galah scars’. Scarring causes massive stress to trees, and consequently the health of many bushland areas suffers. Keeping in mind our bush already has enough to put up with as habitat fragmentation and changing climate bring increasingly dry conditions.

The Galah story gives us an example of how changes to a landscape in one area can cause a native species to become over-abundant, and have large impacts to vegetation and creatures living in another. In bush around Perth now, you will see Galahs occupying many tree hollows, introduced Rainbow Lorikeets taking over the others, and the occasional native Australian Ringneck or ‘28’ squeezing in where they can. Other natives like Red-capped Parrots, Purple-crowned Lorikeets, Elegant and Regent Parrots, as well as a whole suite of LOCAL native birds and mammals, are either totally gone or severely reduced in number. Overall we see a loss of biodiversity, an ‘ironing out’ of the landscape which once had many different shaped and sized ‘bumps’. Each bump is a different plant or animal, responsible for a different task in the ecosystem, and the ‘job losses’ which result from diminished biodiversity are negative impacts to the landscape.

Nature works in weird and sometimes not-so-wonderful ways.

Baudin's are Back!

During the last few weeks, one of our most charismatic birds is returning to the Perth hills in numbers. Baudin's Cockatoo (Calyptorhynchus baudinii) can be heard flying in large flocks and squawking noisily overhead, and if you're lucky you might also see them feeding on plants low in the understorey. This species can easily be confused with the similar Carnaby's Cockatoo - the two are nearly identical to look at and much of their repertoire overlaps, however Baudin's emit a very short 'witcha-witcha' or 'woodchip-woodchip' contact call that gives away their identity.

Baudin's Cockatoos are known among environmental educators as 'the surgeon' because they have a precision tool used for feeding. An extra long upper mandible (beak) helps them probe into the top of the fruit of the local native Marri trees (dubbed a 'honkey nut') and extract the seeds with ease. This is also another feature which can be used to tell them apart from Carnaby's Cockatoos, which have a much shorter upper mandible, and consequently leave behind honkey nuts which have been chewed much more. If you spend some time carefully examining feeding debris, with some practice you can learn how to tell 'who's been there' without having to see or hear the birds.

Here's a female Baudin's Cocky feeding expertly on a Marri fruit in our front yard today - what a thrilling addition to my trip to the mailbox this afternoon!

Big Hooters!

Have you ever listened outside at night and heard strange sounds coming from the bushland? At this time of year, in the Noongar season of Djeran (Autumn), many creatures are becoming active now the summer heat has dissipated. Here's a short video which might answer a mystery about what that funny sound is near your house...


Burrows in the Bush from Simon Cherriman on Vimeo.

These fantastic Hooting Frogs (Heleioporus barycragus) are the largest member of their group, and the largest frog found in the Perth region, reaching a whopping 9cm in length. Four other species can be heard, sometimes all in the same location as Hooters (see this post for more info). They are endemic to (found only in) the south-west of Western Australia, which makes this species even more special. Despite their size and lumpy skin, they should NOT be confused with an introduced Cane Toad (Bufo marinus)! Toads are larger with a very different shaped head, are more uniformly coloured, and have very obvious paratoid (poison) glands on their back. As you can see in the above photo, this fella has no big glands at all! For comparison you can see a picture of a Cane Toad here.

Confusing a large burrowing frog with a Cane Toad might be an excuse for someone in a car to deliberately run one over, but these creatures often get killed accidentally too. I have found several squashed on roads while driving around the hills on humid nights or after rainfall. The message is to keep your eyes peeled and watch the road carefully while driving. Being armed with the knowledge that humid/stormy conditions or rainfall after long, dry periods will bring frogs out onto our roads can make your more alert to animal activity in your area. It's not nice to think that you have killed a male Hooter who is in the middle of a large walk on his way to find a girlfriend!

Using their strong back legs and the specially designed tubercles on their feet, burrowing frogs dig vertically into the ground with amazing skill. Even in hard clay soils interlocked with a mix of roots and reed stems, Hooters have no trouble digging. Once in position, they excavate a small round chamber and begin calling at regular intervals, continuing their unique 'hoooooot...hooooot...' throughout the night.

A male Hooting Frog puffs his throat out while calling from inside his burrow.

If they are lucky and if their calling does the trick, a male Hooting Frog will attract a female into his burrow. He then grasps her in a mating embrace (known as 'amplexus'), and uses large spurs on his forelimbs to grip her firmly. These spurs (see below) are only present during the breeding season, and are a feature possessed by several other Heleioporus species. After mating the female lays her eggs inside the burrow and the tadpoles begin development in a foam nest (as explained in the video above).

Why not put on some warm clothes, grab a beanie and a torch, and take a short bushwalk one evening this Autumn? You might be lucky enough to hear the sounds of burrowing frogs calling near you, and get the opportunity to see one of these frogs up close - an amazing part of our unique natural heritage.

Nest Boxes in Toodyay

This weekend Gill and I had the privilege of running a nest-box building workshop in Toodyay, just east of Perth. Here's how the story went...

The hills were shrouded in mist and glistening dew-drops as we jumped in our vehicle, laden with recycled building material and tools, and followed the winding road heading east early on Saturday morning. After a compulsory coffee-stop in Toodyay, we arrived at a friend's property, surrounded by rolling hills of beautiful Wandoo woodland, to set our equipment up. Georgie Troup, who is a local sustainable agriculture officer with Wheatbelt NRM, was inspired to engage the community and provide some extra breeding sites for Carnaby's Black-Cockatoos. About 70 birds regularly visit the area and at least one breeding site was known. Given the success of my boxes in the Porongurups in encouraging extra breeding pairs, I was as keen as mustard to see if this threatened species would use nest boxes in Toodyay.

About 11 local community members arrived (some of whom had brought work benches and tools galore!), and after a quick cuppa, we began the session with our presentation on tree hollows and creating nest boxes from recycled material. The woodwork soon commenced and the workshop was full of happy voices and the sounds of saws, hammers and drills as the first five boxes took shape. These were designed to be vertically orientated with a section of hollow log on the lid, and 'bee-proof' to prevent invasion by these feral pests. By lunchtime we had all 5 boxes completed and were ready for a great surprise.

Toodyay community members Greg and Vicki get stuck into the woodwork!

Even the kids were keen to be involved!

Phil and Lou from the Kaarakin Black Cockatoo Conservation Centre then surprised us with a lunchtime educational visit. Phil gave a fantastic detailed overview of the status quo of our three species of black cocky, which was made so much more real by having 'Chasey', a real Carnaby's Cockatoo, there in the flesh. Chasey also gave real meaning to our nest box construction - it's not every day you get to have the bird for whom you are building boxes there to watch!

Chasey shows us how Carnaby's Cockatoos dexterously feed on Marri fruit by holding them carefully in their fingers.

Enthusiasm once again filled the air and by late afternoon we had the last five boxes completed. A quick paint job and some afternoon tea to let it dry had us off to the neighbouring properties to hang the boxes. We are looking forward to the landholders keeping tabs on them and letting us know when they have their first residents

If you took part in this workshop and are keen to give us news of the use (by any species) of your nest box, please visit the Re-Cyc-Ology page and comment below the Toodyay post.

A big thanks to all the wonderful, dedicated people who came to the workshop and got involved, especially Rex who traveled all the way from Dowerin. Also, thanks to Georgie and Wheatbelt NRM for organising the day. 

Roadkill

Sometimes finding a dead animal on the road can give us a great learning experience. This picture shows a native marsupial which many of us have never heard of, let alone seen. It is known as a Wambenger, or Brush-tailed Phascogale (Phascogale tapoatafa), one of our most cryptic but fascinating animals. Although I spend much of my time out and about in the bush, both during the day and at night, finding this individual was only the second time I have ever seen one (the other time was also a road-kill victim).

While it might be sad to think about an animal getting killed by a car, this particular victim would have died very soon any way. It was a male - and after each breeding season, all male Wambengers in a population die off. While it may seem strange, this bizarre phenomenon is in fact common among many carnivorous Australian marsupials (a group known as Dasyurids). They do it because it helps boost survival of the next generation by reducing the amount of competition for resources, so newly dispersing young Wambengers, and their mothers, have ample food and nest sites. Also, the fact that mating can be a physically exhausting event which goes on for hours and hours might have some impact on the males' lifespan - I'm surprised more male mammals don't keel over after aggressively mating for 6-8 hours straight!

So - what about Wambengers? Why don't we see them? Like many small to medium-sized marsupials, their numbers have declined since European settlement from impacts like feral cat and fox predation, habitat loss and altered fire regimes. Such large changes have an enormous toll on population size and distribution. However, Wambengers are obviously still around, and are known to exist in areas where native bushland is preserved. They are seldom encountered because they are nocturnal, resting during the day in a well-hidden nest inside a tree hollow, and arboreal, spending much of their night-time foraging period climbing around the canopy. Even if one was out foraging close to the ground while you were out walking through the bush at night, your presence would probably make a Wambenger rush up the tree and hide.

What about food - what do they eat? Having a look at an animal's teeth is a great way to gauge what it eats...

You can see from this picture that a Wambenger's teeth are very sharp and pointy, with 2 obvious canines near the front. This dentition points to a carnivorous diet, one that requires the right tools for lots of chopping up and slicing of food. Morsels munched upon include a variety of animals, from crickets, spiders and cockroaches to geckos and even small birds. Wambengers are also known to eat mice, especially baby ones, so this (together with their insectivorous diet) can make them useful garden additions for keeping pest species down.

There are only a few rare examples of this species living close to human occupation (in buildings and sheds) and making themselves visible. If you like the idea of having a 'native squirrel' living near you which will help munch your garden bugs and has the possibility of revealing its fascinating self to you, then you might like to know some information about how to 'cater' for them. As I said, native bush is a must, although it probably doesn't have to be totally pristine (the section where this fella was found was mostly weedy pasture, except for the numerous native trees left growing. Phascogales also need European predators (i.e. your pet cat) kept under control and inside, especially at night. And lastly, to make their homes they require tree hollows, which can be provided in the form of nest boxes, attached to living trees about 3 metres above the ground. Installing a nest box and checking inside it regularly can be a great way of knowing if you do in fact live close to one of these amazing animals.

Quenda in the Backyard!

Working at night-time and hearing some rustling in the leaves last night drew me outside to investigate. A possum watched me from up in his tree... and a quick spotlight revealed the above photo. After 18 months of living in Mt Helena, we finally have QUENDA in our backyard!  What is a Quenda? It is the local Noongar word for the Southern Brown Bandicoot (Isoodon obesulus), a small marsupial which provides a rare example of a native mammal coping with human changes to the environment. I first saw Quenda when they arrived at my parents' house in Parkerville more than 15 years ago now, and in my experience they have expanded their population since. Even though we had seen Quenda about 500m from our Mt Helena house, the number of stray cats and dogs passing through our property prevented them from living here at the time we moved in. But by deterring these threats and providing native shrubs for habitat we seem to have made the place suitable again.

Here's a quick video of the Quenda in our yard. Such an awesome feeling to have NATIVE MAMMALS sharing your space :-D


Quenda on Camera from Simon Cherriman on Vimeo.

That Pile of Feathers

Ever found a pile of bird's feathers below a shrub, next to your shed, or in some other concealed location in your backyard? Wondered how they got there? Here's a little story which might explain why...

Eating breakfast outside on the verandah this morning was a great way to start the day, and a hive of bird activity made a delightful scene in front of us. New Holland Honeyeater alarms sounded raucously from some bushes at the edge of our block, which drew my attention and had me sneaking over to investigate. There were about four honeyeaters persistently chattering, and as I reached the fence, two magpies dived down and clapped their beaks in aggression. I thought maybe a cat was sitting behind one of the shrubs. Just as I was about to climb over the fence to get closer, I saw a pair of piercing yellow eyes looking back at me. I froze. The eyes belonged to a Collared Sparrowhawk (Accipiter cirrocephalus).

Known as 'Killingilee' in the Noongar Aboriginal language, this small but powerful bird of prey (raptor) is a very swift hunter. The individual in front of me, which I suspected by its larger size to be a female, had killed a Bronzewing Pigeon (Phaps chalcoptera)! It remained perched on its kill for long enough to allow me to grab my camera, and return to take a picture of it. I waited several minutes and was very pleased when it resumed normal behaviour, allowing me to record this at close range. The sparrowhawk plucked many of the pigeon's breast feathers off before starting to eat its kill by tearing small chunks from its body. I watched in amazement, pinching myself that although partly obscured by shrubbery, the bird was still easily visible enough to capture on film.

Sparrowhawks (and goshawks) like to find a concealed spot to kill and pluck their prey.

Small pieces of meat are visible on this Sparrowhawk's beak as she feeds quickly.

It fed for several more minutes, plucking out some of the pigeon's larger flight and tail feathers, then a sudden movement nearby caused it to leap into the air and fly away quickly, carry its meal with it. What amazing luck to see such an unusual event happen right in front of me!

I inspected the pile of Bronzewing feathers, and noticed (as I have done with the many raptor kills I've seen before) that the pile consisted of mostly smaller body feathers and a few larger ones from the wings and tail. It was a good opportunity to observe the differences between a raptor kill and that of a mammal like a Fox or Cat.

• To expose the meat and help them feed easily, raptors take care to pluck most of the finer feathers, which Foxes and Cats may not bother doing.
• Having a hooked bill, raptors are able to pluck feathers neatly, leaving them intact. Foxes and Cats usually chew feathers in half, so you will find the longer ones snapped or sheared at the edges.
• Raptors often feed by standing in the one spot, and unless the wind blows them around, features remain in a neat pile. Mammal predators often drag or wrench their food around in many directions, making a bigger mess.
• Small pieces of meat and internal organs (such as the crop and stomach in the above Bronzewing) are sometimes left behind by raptors, as a product of their more delicate feeding method.

Next time you find a pile of feathers, take careful note of where they are and what they look like - you might even be able to reassemble an interesting story like mine!