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[Nocturnal Animal Guides] [Spotlighting
Information] [Possums Page]
[Lakes Eacham & Barrine Native Mammal List]
Most Australian Rainforest Wildlife are
Nocturnal animals.

- Spotlighting equipment is available for the
guests to view any Australian Nocturnal Rainforest Animals that don't visit the
lodge railings.
- Your host, John Chambers, has excellent
suggestions on which areas of the rainforest you can go spotlighting for
nocturnal wildlife such as:
Lumholtz Tree Climbing Kangaroos,
Lemuroid Possums, Ringtail Possums and
Green Possums.
- Whether you're seeking an active Australian
Wildlife Eco Adventure holiday or a private, solitary, rainforest retreat
Chambers Wildlife Rainforest Lodge
at Lake Eacham in The Waterfalls & Crater
Lakes District of the Atherton Tablelands near Cairns and the Great Barrier
Reef, is an idyllic destination,
but DO allow at least three days, preferably a
week or more, to do it justice.
Additional Information on
Nocturnal Animals:
Nocturnal Animals
- Why are so many animals nocturnal? Why not? As
mammals who function by day, we are in the minority.
- But as a top predator we
have little need to hide.
- Most Australian mammals – as well as insects, small
reptiles and frogs – are potential meals for something else so it is to their
advantage to function under cover of darkness, when many predatory birds and
reptiles are asleep.
- But where there is potential food, there are
potential predators.
- Although most birds are diurnal, owls feed by night and for
pythons, cool night time conditions are ideal for hunting. Nonetheless, night
is, on balance, safer for many.
- From the predators’ point of view, night offers
the opportunity to take advantage of food which is unavailable by day – from
nocturnal mammals to worms which come to the surface.
- Competition is also
reduced – owls do not have to compete with diurnal birds of prey and frogmouths
and nightjars can take the place of swallows, swifts and flycatchers.
- In Australia, avoiding the sometimes searing
daytime temperatures is an additional advantage for many animals, reducing their
need to conserve water. (Source: Environmental
Protection Agency)
- The nocturnal habits of many mammals possibly
date back to when they evolved from reptiles in the time of the dinosaurs. As
they were warm-blooded, they were able to function during the night when
reptiles – probably their main predators – became inactive.
- To move more quickly at night, mammals
sometimes leave scent trails using special glands, so they can travel along
familiar routes with ease.
Night Signs
- It may not be easy to find animals at
night. Signs of their presence however may give good clues as to what is there
and what is nearby.
- Usually in groups,
Pademelons browse on the grass in rainforest clearings. Evidence of their
presence includes chewed rasp ferns and Smilax vines along tracks. A loud
warning thump may be heard as an indication you have startled one. Guests at
The Chamber’s can view these animals nightly in the clearing outside the
lodges whilst listening to a commentary.
- The sound of crunching and cracking into
hard nuts is likely to be from a White-tailed Rat. It is just as likely to be heard in a tree as on the
ground as it is a good climber. Outside The Chamber’s Lodges, the white-tailed
rats can be seen as they feed from the railings on a regular basis.
- Bandicoots
dig holes in the ground while searching for invertebrates. The long-nosed
bandicoot makes generally deeper and more conical holes than those of the
northern brown bandicoot. The northern brown bandicoot prefers clearings while
the long-nosed bandicoot prefers deeper rainforest and higher areas.
- A loud rasping call is produced by mist
frogs, and a loud clucking call is produced by waterfall frogs. Pond
frogs are noisier. The best way to find a frog is for 2 or 3 people with
torches to shine them at the spot from which they think it is calling. It is
then likely the frog will be near where the beams intersect.
- The sounds of cicadas, katydids and crickets
are commonly heard in the rainforest at night and often easily seen at The
Chamber’s.
- The presence of a
Striped Possum may be indicated by gouged logs and a strong musky smell.
They dig out wood-boring grubs with their long incisors (similar to actions of
the white-tailed rat).
- A spotlight often shows the glistening of
spiders’ eyes. Usually, those active at night are dull coloured, well
camouflaged spiders that hide under bark or in burrows during the day.
- Brown
Tree Snakes are nocturnal (unlike green tree
snakes). They eat sleeping birds, lizards and frogs, which possibly attract
them to the ground level.
- Luminous Fungi
are often seen in the rainforest when the lights are turned off. They may glow
to attract gnats that disperse their spores, although no one is certain why
they glow.
- Blinks of light from fireflies are
mating beacons as the males and females of these beetles signal to each other.
The light given off by the chemical reaction becomes brighter when more oxygen
is present. This means flying ones are brighter than stationary ones.
- Insectivorous bats
can be seen darting around creeks and other water bodies.
- A
Leaftail Gecko may be seen, as they prefer to hunt at night unlike
most lizards. Torchlight high on a tree trunk may catch the two bright eyes
belonging to one of these creatures.
- A glowing dot beneath a creek or track bank
may belong to a glow-worm (the larva of the fungus midge). Look for dangling
sticky lines, ready to catch small insects attracted to the light.
- Fish, eels, yabbies and other creek dwellers
are sometimes active at night. To find their way around, fish use lateral
lines – fluid-filled tubes under the skin along the side of the body connected
to the body via pores. Extensive whiskers of catfish are used to touch and
taste too.
- The loud and mournful calls of
Orange-footed Scrubfowls may be heard as they defend their
territory from roosts on high branches.
- Owls, often with
silent flights due to the soft fringes on the edges of their feathers causing
a break-up of the airflow and muffling of noises, are silent night hunters.
They eat rodents, bandicoots, bats, possums, birds, birds, geckos, frogs and
invertebrates.
- The
Southern Boobook Owl southern boobook owl often does not fly off when
people walk by. Instead, it stands upright, its feathers tightly pressed
against its body, and turns side on to the person to give it a very long,
slender appearance.
southern boobook owl southern boobook owl
often does not fly off when people walk by. Instead, it stands upright, its
feathers tightly pressed against its body, and turns side on to the person to
give it a very long, slender appearance.
- Rather than rainforests, toads prefer open
grassy areas. They have a bright eyeshine and blink often.
- Splatters of white droppings on the ground may
be the indication of a roosting bird above. When it sleeps, it is vulnerable
to attack from snakes, so many perch at the ends of thin branches. This gives
it a warning, as the weight of an approaching snake will shake the branch.
- Possums
often drop chewed leaves. Herbert River ringtails prefer secondary regrowth
and sometimes make their dens in epiphytic ferns. Green ringtails and
brushtails feed on secondary and pioneer species, while the lemuroid ringtails
prefer the higher canopy level of primary forest.
- Loud squabbling noises from
Flying Foxes may be heard in the rainforest. These bats usually press the
fruit against the roof of the mouth to extract the juice and then spit out the
remains, which can be found under popular feeding trees.
- Churned-up earth is an indicator of favourite
feeding sites of feral pigs in the rainforest. These animals are
potentially dangerous, so be careful.
Eyeshine
- Many nocturnal animals have eyes that are adapted
to low light conditions.
- Because of this, they are easier to find with a
spotlight at night.
- Light passes through the retina when it enters our eyes.
Some of this light is absorbed, and some of it is lost in the background
tissues.
- Many nocturnal animals have what is known as a tapetum, which is a
mirror-like membrane situated behind the retina, which reflects the light back
through the retina again.
- The light that we see reflected in our spotlights is
the remainder of this light that passes out through the eye again.
- Different animals produce a different brightness
and colour of eyeshine.
- Humans, as seen in flash photographs, have a dull red eyeshine. This is an indication of our poor night vision. In contrast, cats are
known to have good night vision as their eyes produce a bright reflection when
caught in the headlamps of a car.
- Possum-spotting experts can often tell which
species of possum they are looking at simply by their eyeshine colour.
- The
Herbert River ringtail has a pink or yellow eyeshine, the green ringtail has a
dull red, brushtails and striped possums have a pinkish eyeshine, and lemuroid
possums have the brightest eyeshine of a white or yellow glare.
- Tree-kangaroos
reflect only a dull red shine, but spiders, geckos and many other nocturnal
animals have eyes that glisten or sparkle.
- Rod cells are the cells that dominate in
nocturnal animals’ eyes. They contain a very sensitive chemical called
rhodopsin. This breaks down in a process that sets up electrical impulse
transmissions to the brain when light reaches it. The rhodopsin is rebuilt
instantly using vitamin A as soon as it breaks down so vision can be continuous.
Large rod cells contain more rhodopsin, but fewer can be packed into a given
area, which means there is a consequent reduction in visual detail.
Spotlighting
It is important to try to minimise the
impact on the wildlife while still maximising the satisfaction of participants
when spotlighting. Some points to consider: -
- Group size should be no more than 12.
- Noisy or rowdy behaviour is unnecessary.
- Use individual torches for safety only.
- Do not shine spotlights on nesting birds or on
any person.
- Once an animal has been found with a
spotlight, the light will usually disturb it, so it is best to quickly cover
the light with a filter.
- Minimise the number of vehicles – no more than
2.
- When encountering another vehicle, turn off
spotlights and torches until well clear.
- Only use standard vehicle lights to illuminate
the road.
- Connecting a telescope to a TV monitor inside
the vehicle reduces disturbance and is useful to less able walkers.
- Wildlife should not be provoked, fed, handled
or interfered with deliberately.
- Captive wildlife and domestic pets should not
be taken on spotlighting tours.
- Recording any wildlife observations is useful
to assess any changes over time and to see the impact of spotlighting upon the
resident wildlife population.
- Nocturnal animals’ eyes are very light
sensitive. Using filtered lights of less than 30W will increase both the
chance of finding an animal and the length of viewing the animal (they are
less likely to move away). Brighter bulbs warn the animals of the approaching
people. A filter could be a piece of red cellophane.
- Tree-kangaroos are very sensitive to light,
even with red filters. To keep disturbance at a minimum, it is best to double
the filter.
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