Big moth numbers dwindle

sorts of habitats from the coast to upland moor, from woodland to private gardens, with about 85 traps running each year. But the cash-strapped institution has had little funds to analyse the mountain of data generated. So in 2003, the British charity Butterfly Conservation together with Rothamstead Research, with funding from the Esmee Fairbairn Foundation, launched a collaborative project to examine this dataset and develop the first national population trends for individual moth species. The first result to emerge was that the total number of larger moths being caught by the Rothamstead traps had declined dramatically. A third fewer moths are around in British countryside now compared with the late 1960s. An alternative explanation, that traps had become less successful at attracting moths due to increasing light levels was investigated and found to be untrue. So this result demonstrates that, like butterflies, moths have undergone widespread declines. The worst affected species have declined by more than 90 per cent and 75 out of the 337 larger moths have decreased by more than 70 per cent. Overall, two thirds of the species studied declined. Many birds eat moths and moth caterpillars and all British species of bat feed on moths, as do other small mammals and many invertebrates. Other studies have shown that more than 70 per cent of butterfly species have declined over the same period. " Together, the declines of so many moths, and butterflies, signal a severe crisis for British biodiversity and one that will only be reversed with landscape-scale restoration of habitats, " the report says. A new analysis* of British moth numbers recorded in one of the best datasets in the world over the past three and a half decades has revealed some alarming results: many large species appear to be in dramatic decline. The data have been generated by Rothamstead Research in Hertfordshire, the world's oldest agricultural research station, which has been coordinating a national network of moth traps since 1968. All the traps are of a standard design, making direct comparison possible between sites over time. The traps operate every night of the year and all moths are identified, counted and then released. Rothamstead traps catch small but representative numbers of moths, which ensures that the monitoring is effective without damaging the moth populations being studied. Since 1968, traps have been operated by volunteers at over 430 sites in all Big moth numbers dwindle …