Nature diaries show subtle climate changes

ANOTHER LIFE:'OAK BEFORE ash, bit of a splash; ash before oak, wait for a soak" – perhaps they just liked rhyming. Here at Thallabawn, oak and ash were neck and neck this spring, buds slowly swelling through the glittering April weather. The ash pipped the oak by a morning, unzipping black purses to a peep of folded leaves. Another brilliant day and there were swallows arced against the mountain and our first peacock butterfly, basking eye to eye with the sun.

Remembering for once to make a note in the National Gallery Diary 1988 that I use for these things (hard covers and lovely paintings – “All Sorts of Flowers”), I found the first swallows down for the same date, April 19, in 1996 and 2001.

This is the earliest ever for Thallabawn, but, this spring, an advance guard of swallows reached the east coast of a chilly and virtually insect-less Ireland as early as mid-March. Even as global rhythms respond to climate change, a regionally atavistic winter can catch nature out.

My nature diary is a scrappy, impulsive notebook and nothing to compare with the phenology of proper naturalists. Indeed, as a recent scientific paper noted: “In Ireland, the systematic recording of phenological events has not traditionally been undertaken”. It’s the systematic bit that counts, and we have nothing to match the amazing nature diaries kept assiduously, generation after generation, by certain landed families in Britain, and reaching back over 300 years.

In the early 20th century, however, the Irish Naturalists’ Journal did publish some 10 years of records – more than 25,000 observations of such things as first flowering of plants and leafing of trees, first arrival of summer migrants, first birdsong, first insect, and so on.

Matched to temperature, they showed that the response to spring warming in Ireland was, if anything, greater than in Europe, especially in plants.

There are also the records kept on special groups of trees at the four “official” phenological gardens in Ireland: Valentia, Co Kerry; the JFK Arboretum and Johnstown Castle in Co Wexford, and the National Botanic Gardens in Dublin. As part of a Europe-wide network, they were planted some 40 years ago with clones of tree and shrub varieties, to see how virtually identical plants would respond to local climates. They have shown trees such as beech and poplar leafing much earlier in spring than they were 30 years ago.

It is with this sort of data, and local and field-club records of birds, moths and butterflies, that researchers at Trinity College, funded by the Environment Protection Agency, have been working to use phenology as an indicator of climate change. They also need to study the extent to which earlier springs and other rapid seasonal changes are throwing vital natural links out of synchrony – birds with the peak food supply of caterpillars for their young, for example.

Because Irish phenology has been so limited in its species and locations, the Trinity team, headed by Dr Alison Donnelly and with the help of the National Biodiversity Data Centre at Waterford, have opened a special website (http://phenology.biodiversityireland.ie) where they hope “citizen scientists” can be encouraged to record their phenological sightings through the year.

This follows the pioneering example of Co Cork naturalist and computer expert Paul Whelan, who in 2005 set up biology.ie, a website for recording such sightings on interactive maps.

It also runs or publicises the increasingly wide range of biodiversity surveys, from the Kerry slug to squirrels and butterflies.

An Irish county with special interest in keeping its eyes open this spring and summer is Co Wexford. At the island’s southeast corner, it is becoming a potential bridgehead for new species prospecting or colonising Ireland from the south as the climate warms. The emperor dragonfly, big and blue above Wexford’s lakes, has been a spectacular settler.

The probability of another, the frayed-looking but beautiful Comma butterfly (pictured but invisible as a dead leaf when its wings are closed), is discussed in the new Lepidoptera of County Wexford, published by the Wexford Naturalists’ Field Club at €10. This gallery of the county’s butterflies and moths, a labour of love by Michael O’Donnell and Christopher Wilson, voices “the strong suspicion” that Commas have now bred in the Raven Nature Reserve.

The sensitivity of butterflies to climate and their role in marking biodiversity motivate the monitoring scheme of the National Biodiversity Data Centre. It seeks more volunteers to walk a fixed route through several habitats once a week from April to September, recording the butterflies they see.

A workshop to brief volunteers will be held on May 15th at Fota Wildlife Park in Co Cork.

EYE ON NATURE

I watched as a starling tried to pull some primroses apart in my garden. It eventually flew off with some purple flower heads. I’m not sure if these were to line a nest or make a bower.

Richard Murphy, Beechfields, Dublin, 15

The male starling builds a rough nest and sets out to attract a female. When he succeeds she finishes off the nest with softer material. But the male brings petals and green leaves to decorate it.

Recently my granddaughter and I saw a little lizard in Galway city suburbs, yellow/green with black spots. Are they common here?

Eileen White, Roscam, Galway

It was a viviparous or common lizard, the only one native to this country.

While rock-pooling at Seapoint, my daughter Naoise found a live octopus about 30cm in diameter. How common is this?

Tom Richardson, Dún Laoghaire, Co Dublin

It is not unusual and they usually get washed out to sea again by the tide.

While opening a garden parasol that has been in storage since last year I saw four wasps which came to life with the warmth. What is the longevity of a wasp.

Janet McEvoy, Causeway, Co Kerry

Worker wasps die in autumn. Only queens hibernate and start a new brood in spring.

Michael Viney welcomes observations at Thallabawn, Carrowniskey PO, Westport, Co Mayo. E-mail: viney@anu.ie. Include a postal address.