A zoo without bars by Dr Lisa Holmes

A zoo without bars –

Building thoughtful habitats

for all to explore.

Chester Zoo (www.chesterzoo.org) is a registered conservation and education charity that supports projects around the world and closer to home in Cheshire. Welcoming 1.9 million visitors a year, it is the most visited zoo in the UK; home to over 15,000 animals and more than 500 different species, many of which are endangered in the wild.

Chester Zoo has continued with the ‘always building’ philosophy of our founder, George Mottershead, who created the UK’s first zoo without bars and focused on animal wellbeing and conservation. In 2015 Chester Zoo opened Islands which was the largest zoological development in the UK to date. The Islands expedition is an immersive experience, taking visitors through six South East Asian islands to discover the incredible wildlife native to those areas and highlight the conservation issues that the zoo staff are working hard to address.

Modern day zoo research encompasses many aspects of biological and social sciences with the overall aim to address challenges faced in the natural world. Chester Zoo not only supports conservation research both in- and ex-situ but leads on important projects both in the UK and across the globe to improve the management of animals and plants, influence sustainability of wild populations and inspire others to Act for Wildlife.

Lisa Holmes is the Behaviour and Welfare Scientist within the Applied Science team at Chester Zoo. Her role involves working closely with the animal curators and keepers to provide evidence-based recommendations to enhance animal wellbeing and help to inform enclosure design. Lisa supervises postgraduate and sandwich placement students who help to gather key data for a wide range of species. Lisa’s research team are currently working on a long-term project assessing the response of species which have moved into the new Islands habitats.

Check out Lisa’s latest sciku ‘The Masterplan’ here.

Plenty of fish

Plenty of fish yet

male voles choose monogamy

… but do their partners?

 

Monogamy is relatively rare in the animal kingdom, with extra-pairs matings happening a lot more than you might think. Males in particular are thought to gain the most from polygamy by being able to sire multiple offspring, whilst females may gain from monogamy through defence or paternal care of their young.

Yet despite having access to multiple females, male prairie voles choose to form exclusive pair bonds with individual females (Blocker & Ophir, 2016). In contrast,  female prairie voles readily engage in promiscuous mating (Wolff et al, 2002).

So why (under laboratory settings) are male prairie voles monogamous whilst females are promiscuous?

Blocker & Ophir, 2016 argue that one explanation could be that the costs to males of trying to hang on to multiple females at once are too great, and that male prairie voles gain the most by aggressively monopolising just one female. Females on the other hand have nothing to lose from polygamy so will mate with other males if the opportunity presents itself.

In prairie voles it seems that monogamous behaviour may be male-driven.

Foundress

Paper foundress queens

Influence their colony

In character and size.

 

We often look for similarities between ourselves and our parents/children, in the way we look or behave. In paper wasps the personality of the queen influences the size and aggressiveness of the colony they found: Bolder queens tend to produce more workers that as a colony are less likely to attack a simulated agonistic stimulus, however whilst shyer queens tend to produce a more aggressive colony with fewer workers. Wright et al, 2017.

The drink of the gods

The drink of the gods

curbs oxidative stress through

clever conversions

 

The energetic demands of flying causes muscular oxidative damage. Whilst some foods have antioxidants, nectar doesn’t – a potential issue for flying nectar-feeding animals. To get around this issue hawkmoths appear to be able to “generate antioxidant potential by shunting nectar glucose to the pentose phosphate pathway”. Levin et al, 2017.

Immigrant crabs

Immigrant tree crabs

Move from mangrove to salt marsh

…but it’s not the same.

 

Mangrove tree crabs have responded to climate change by moving northwards into a novel habitat: salt marsh. The crabs used to show site fidelity in their historic habitat but the faecal cues they used for this are now often washed away in the salt marsh which is regularly flooded. Climate change may therefore be indirectly affecting foraging behaviour and predation risk. Cannizzo & Griffen, 2016.

Original research: https://doi.org/10.1016/j.anbehav.2016.08.025

 

Gregarious sharks

Gregarious sharks:

Cohabiting siblings and

multiple lovers

 

Whilst the bluntnose sixgill shark is a widely known species of shark, little is known about its biology. A genetic study looking at polymorphic microsatellites revealed that individuals sampled at the same time and place were often siblings, whilst one female was found to have had up to 9 males fathering her offspring. Larson et al, 2011.

Road-safety

Road-safety crucial:

Engine noises distract from

predator odours.

 

Noise pollution can have a number of effects on wild animals. Morris-Drake et al (2016) found that road noises meant that dwarf mongooses were slower to detect a predator odour and did not increase vigilance in response to the odour (whilst mongooses exposed to normal ambient noise found the odour faster and showed increased vigilance).

Lugging worker

Lugging worker ants

use a celestial compass.

Is this a moonwalk?

 

Ants often need to walk backwards when dragging heavy food items to their nests, but how do they navigate when moving in reverse? Rather than relying on visual memories of terrestrial cues, ants instead use their celestial compass – this can be disrupted by presenting ants with a mirror image of the sun’s position in the sky. Schwarz et al, 2017.

Original research: https://doi.org/10.1016/j.cub.2016.12.019

Perfect storm

Spreading fungal scourge

salamanders succumbing

perfect storm draws near.

 

Many of the world’s amphibians are under threat from a chytrid fungus (Bd), particularly in the tropics where it is driving many amphibian species towards extinction. More recently a sister species (Bs) has been observed in Western-European salamanders. Observations of a salamander population across two years following initial detection of Bs suggest a rapid population collapse with little recovery. Bs also has an increased transmission strategy over Bd and may behave as a “perfect storm” as it spreads through European populations of salamanders. Stegen et al, 2017.

When courting

When courting with song

do take turns with your neighbour –

Gentlemen hermits!

 

Male long-billed hermits (a sub-group of humming birds) form leks to attract mates by singing, but competing birds close together could overlap singing and confuse each other’s song. To counter this, males close together coordinate to alternate singing bouts whilst males further away from each other (and not at danger from vocal obscuration) overlap their songs. Araya-Salas et al, 2017.