To listen to RTÉ.ie's radio and podcast services, you will need to disable any ad blocking extensions or whitelist this site.
Panel: Terry Flanagan & Niall Hatch, with pre-recorded reports from Richard Collins & Éanna Ní Lamhna
There has definitely been a change across Ireland over the past week or so. Temperatures have suddenly dropped, the leaves are starting to wilt and shrivel on the trees, migrant birds are arriving and departing at a faster rate each day and butterflies have become much harder to find. Autumn is well and truly here . . . which is fine by us here at Mooney Goes Wild. After all, it's one of the most interesting times of year from the point of view of wildlife, so why not get out and about over the coming days and experience this fascinating season of natural transition for yourself?
Is our warming climate causing some animals to "shape-shift"?
We have spoken many times before on the programme about the problems that climate change poses, not just for us humans, but for plants and animals. As global air and water temperatures rise, it seems certain that many organisms will either struggle to survive or will be required to adapt very rapidly to the changed circumstances in which they find themselves. For some, this may necessitate moving to colonise new areas, learning to exploit new food sources or trying to cope with increased competition from other 'climate refugee’ species.
Masked Shrew - Sorex cinereus. (Photo by: MyLoupe/Universal Images Group via Getty Images)
For others, however, natural selection may allow them to change their body shapes in order to fit in better to their new world. Indeed, this seems already to be happening to several different animal species, and over a much shorter time period than such evolution would normally occur, as researchers from Deakin University in Australia have discovered.
Particularly strong evidence of "shape-shifting" has been reported in some birds. For example, several species of Australian parrot have shown, on average, a 4%-10% increase in beak size since 1871, and this is positively correlated with the increases in summer temperature each year. Similarly, studies of Dark-eyed Juncos, small sparrow-like songbirds from North America, have revealed links between increased beak size and short-term temperature extremes in cold environments. Changes have also been reported in some mammals; for example, tail-length increases in Wood Mice and tail- and leg-length increases in Masked Shrews.
Dark-eyed Junco. Pic Getty
But why? Well, the larger the appendages of an animal, the greater its ability to regulate its body temperature in warm environments by dissipating excess heat. Natural selection appears, in some cases at least, to be favouring individual creatures with, say, slightly larger beaks, legs or ears, features which may increase their survival chances in warming environments. As our panellists discuss on tonight’s programme, however, this does not mean that these evolutionary changes are necessarily in the best long-term interests of these animals. They may, for example, have long-term implications for their ability to feed or breed successfully: it’s still too early to know for sure.
For more information on the findings by the Deakin University researchers, visit sciencedaily.com/releases/2021/09/210907110718.htm
Oh what a tangled web we weave
No group of animals provokes such a strong reaction amongst Mooney Goes Wild listeners as spiders: some of you are very fond of them, while many of you seem to despise them. Love them or loathe them, there is no denying that they form a crucial part of our ecosystem. They are also deeply fascinating animals which, once you get to know them, are revealed to be extremely impressive and even beautiful.
Garden Crows spider in Terry Flanagan's garden. Pic Terry Flanagan
One of the most beautiful things of all about spiders has to be the intricate silk webs which many species spin. Spider silk is a true marvel of natural engineering. It is extraordinarily light, yet has a higher tensile strength than steel, allowing it to bear loads that are hundreds of times its own weight. What’s more, it is naturally adhesive and superbly flexible: a wonder material, if ever there was one. The fact that spiders can, with seemingly little effort, coax it into some of the most gorgeous forms in nature is the icing on the cake.
On tonight’s programme, Derek and the panel discuss a stunning spider web that he discovered on the wing-mirror of his car. It transpires that this was the work of an orb-web spider, a group of arachnids that build particularly impressive webs in which to ensnare their prey. Specifically, judging by the open, strand-free segment at the top of the web, which you can see quite clearly in Derek’s photo here, it appears to be the handiwork of the oddly but aptly named Missing Sector Orb Weaver spider.
The spider web on Derek's car. Pic Derek Mooney
In order to learn more about spiders, Terry Flanagan recently met up with TCD zoology research associate and renowned creepy-crawly-lover Collie Ennis to discuss these fascinating, under-appreciated and much misunderstood creatures.
For more information about Collie Ennis’ scientific research, visit researchgate.net/profile/Collie-Ennis
Sticking their necks out: giraffes and the ‘grandmother hypothesis’
We humans are an unusual species, in that the average lifespan of females significantly exceeds their reproductive period. Unusual, but not unique. A small number of other animal species, including elephants and orcas, benefit from what has been dubbed the ‘grandmother hypothesis’: post-menopausal females experience an evolutionary benefit by helping to care for their grandchildren, as this behaviour increases the survival chances of their own genes.
Giraffe in the savannah, Botswana. Pic Getty
Until now, it was believed that giraffes, unlike primates, elephants and cetaceans, had little to no social structure. However, new research has revealed that female giraffes also go through the menopause early, spending up to 30% of their lives in a post-reproductive state, in order to help to care for their descendants. It transpires, contrary to previous assumptions, that they are highly socially complex creatures, and exhibit many features typical of female-dominated societies.
On tonight’s programme, Richard speaks to Dr. Zoe Muller, giraffe expert at the University of Bristol and co-author of the research that has uncovered these surprising findings. Zoe tells us about the unexpectedly complex social and familial relationships of these long-necked giants, explains just how the ‘grandmother hypothesis’ appears to operate, and questions why such a large, iconic and charismatic African species has been understudied for so long.k
For more information on these fascinating findings about giraffes, visit onlinelibrary.wiley.com/doi/full/10.1111/mam.12268
Freshwater Pearl Mussels
What Irish animal has the longest life-span? It’s not us humans, nor any kind of mammal, bird, reptile, amphibian, fish, insect or arachnid: it’s an unassuming, often overlooked creature called the Freshwater Pearl Mussel. These river-dwelling molluscs can live for as long as 180 years, but despite their longevity, as a species they are in serious trouble and are at risk of extinction. During the course of the 20thcentury, it is estimated that Europe lost 90% of its Freshwater Pearl Mussels, victims of water pollution, disturbance and introduced alien invasive species.
In 2013, it was estimated that the Republic of Ireland was home to 12 million of these remarkable freshwater shellfish, then representing a staggering 46% of the remaining EU population. In the mere 8 years that have passed since then, however, the Irish population of these mussels has declined by a shocking 20%-38%.
If these trends continue, we could be looking at the total extinction of this highly vulnerable species across Ireland in the space of just a few decades, as has already happened in countries such as Poland and Denmark. This would be a tragedy, not just because of the loss of such a remarkable and long-lived species, but because the Freshwater Pearl Mussel is a "keystone" species, playing a unique and irreplaceable role in the filtration of our inland waterways that benefits vast numbers of other animals and plants.
The freshwater pearl mussel (Margaritifera margaritifera) Pic npws.ie/research-projects/animal-species/invertebrates/freshwater-pearl-mussel
On tonight’s programme, Éanna talks to Richard O’Callaghan, manager of the KerryLIFE project for the National Parks and Wildlife Service, about the international importance of our surviving populations of Freshwater Pearl Mussels, the threats facing them and the measures being taken to try to ensure their continued survival.
For more information about Freshwater Pearl Mussels in Ireland, visit npws.ie/research-projects/animal-species/invertebrates/freshwater-pearl-mussel
For more information about the KerryLIFE project, visit teagasc.ie/environment/biodiversity--countryside/research/current-projects/kerry-life/
Coastwatch Autumn Survey
Since 1987, the non-governmental organisation Coastwatchhas been engaging eager volunteers to assist with its annual All Ireland Coastwatch Survey, which is designed to give an overview of the state of our coastline. This takes place each autumn, and this year will run until 15th October.
Tranarossan Beach in Rosguill, Co. Donegal. Pic Getty
If you would like to become a 'citizen scientist' and help to gather data on a coastal area near you, Coastwatch would love to hear from you. Their special survey website allows you to choose your own preferred section of coastline and contains all the information you need to get started and to identify the different plants and animals you may find during your survey. You should plan to begin your survey approx. 1 or 1.5 hours before high tide, and the data you gather will be of enormous use in the assessment of our vital coastal habitats.
For more information about the Coastwatch survey and to register to take part, visit coastwatch.org/europe/survey