Skip to content

Nature

Bat predation is affected by odour

by Colin Ricketts 02 May 2013
Bat predation is affected by odour

This is the Australian long-eared bat, Nyctophilus geoffroyi, captured purely for a bit of guano! - Credit: © Tracy Morris

Accumulation of smells can attract a lot of attention of the wrong kind, as we all know. For tree-roosting bats, the confined spaces they inhabit need to be swapped frequently, so that they can avoid detection by predators. This is the idea that some Australian researchers tested in these observations in Sydney.

Although the removal to alternative roosts would reduce the thermoregulation advantage of staying put, it would also help reduce the parasitic load and maintain any social relationships between the bats' colonies. During the research, various predators nosed out some of the 90 artificial "roosts" with bat faeces present and significantly less of those without faeces.

Sydney Harbour National Park holds several insectivorous bat species, such as the lesser long-eared bat above or Gould's wattled bat that roost in some buildings, caves and the hollows of tree stumps. The faeces was collected from locally trapped bats (see the photograph) and distributed around 30 solitary "roosts," 30 group "roosts," and omitted from 30 control "roosts."

Dr. Caragh Threlfall, Bradley Law and Peter B. Banks of the Universities of New South Wales and Sydney, as well as the Forest Science Centre (in Beecroft) set up the roosts and wrote a paper they publish now in Biology Letters.

We must thank them, especially Dr. Threlfall for supplying the photographs. The visitors to the artificial roosts included, in order of visit frequency, ringtail possums, Pseudocharus peregrinus, black rats, Rattus rattus, and pied currawongs - birds related to the Australian magpie, called Strepera graculina. Snakes would also be expected to predate these bats, but were not found in the observations.

The results indicated that the smallest amount of bat guano or faeces would result in increased predatory risk. The faeces of a single bat increased predator visits by 30% after just 1 day (after 2 days, 44%). The increase in visits therefore mainly took place on the first day.

Although bats choose the least risky roosts, predation at roosts has reduced bat populations drastically. Roosting with other bats reduced predation risk, because more guano surprisingly reduced the predators' visits. Infra-red cameras and indirect roost entrance disturbance were used to detect predators. The result was a surprising number of possums and this black rat found the smell quite inviting!

This rat entering the bucket gives an idea of the

This rat entering the bucket gives an idea of the "roost" setup which was entirely artificial. No bats included; Credit: © Shutterstock


Trending Eco-Friendly Clothing

Love My Planet Women's Relaxed Fit Hoodie
Earth
Quick Add
Close
Notify me
Notify me
Love My Planet Women's Relaxed Fit Hoodie
Love My Planet women's eco-friendly relaxed fit hoodieSize Guide Centimeters 8 10 12 14 16 18 Bust 84 88 92 97 103 108 Waist 66 70 75 80 85 91 Hips 91 95 99 104 109 116 Bust: Measure around the fullest part of...
£38.00
£38.00
Close
Notify me
Notify me
Penguins Hate Push-Ups Men's Pullover Hoodie
Earth
Quick Add
Close
Notify me
Notify me
Penguins Hate Push-Ups Men's Pullover Hoodie
Penguins Hate Push-Ups men's eco-friendly pullover HoodieSize Guide Centimeters XS S M L XL XXL Height 171 175 179 183 189 195 Chest 86 93 99 104 116 129 Waist 71 76 81 89 99 112 Chest: Measure all round your chest just below...
£38.00
£38.00
Close
Notify me
Notify me
Lightning Bolt Kids Long Sleeve T-Shirt
Earth
Quick Add
Close
Notify me
Notify me
Notify me
Lightning Bolt Kids Long Sleeve T-Shirt
Lightning Bolt kids eco-friendly long sleeve t-shirtSize Guide Centimeters 3-4yrs 5-6yrs 7-8yrs 9-10yrs 11-12yrs Height 98 112 125 136 147 Chest 60 66 70 75 84 Chest: Measure all around your chest just below your armpits. Height: Your natural height If you fall between...
£18.00
£18.00
Close
Notify me
Notify me
Notify me
Union Jack Tote Bag
Earth
Quick Add
Close
Notify me
Notify me
Union Jack Tote Bag
Union Jack eco-friendly colour tote bagProduct Specification Organic Cotton Tote Bag. Twill Weave (170gsm). 37 x 42 cm (7cm gusset.) Made in India / Designed on the Isle of Wight. Wash Cool, Hang Dry.
£16.00
£16.00
Close
Notify me
Notify me
Prev Post
Next Post

Eco-Friendly Shop

Women's Clothing

Eco-Friendly Clothing for Women Our online shop offers a wide range of sustainable women’s clothing products, including t-shirts, hoodies, vests, sweaters, shorts, and...
Shop Now

Men's Clothing

Eco-Friendly Clothing for Men Our online shop offers a wide range of sustainable men’s clothing products, including t-shirts, hoodies, vests, sweaters, shorts, and...
Shop Now

Kids Clothing

Eco-Friendly Clothes for Kids Our online shop offers a wide range of sustainable kids clothing products, including t-shirts, hoodies and jumpers. Our garments...
Shop Now
Someone recently bought a
[time] ago, from [location]

Thanks for subscribing!

This email has been registered!

Shop the look

Choose Options

Earth Times
Sign up for exclusive updates, new arrivals & insider only discounts

Recently Viewed

Edit Option
Back In Stock Notification
this is just a warning
Login
Shopping Cart
0 items

Before you leave...

Take 20% off your first order

20% off

Enter the code below at checkout to get 20% off your first order

CODESALE20

Continue Shopping