The Numeniini — a tribe of large waders including curlews and godwits — is one of the most threatened bird groups on the planet. The once-abundant Eskimo Curlew Numenius borealis of the Americas is now considered Critically Endangered (Possibly Extinct), having last been spotted with certainty in the 1960s. Like the Eskimo Curlew, the possibility of the extinction of the Slender-billed Curlew (Numenius tenuirostris) cannot be confirmed for sure until we have scoured the entirety of its known breeding grounds in the Siberian wilderness for a remnant population.
Buntings are a group of Eurasian and African passerine birds of the family Emberizidae. Insect food sources must be available to them for reproduction. Their populations are in peril since the introduction of neonicotinoid insecticides in agriculture, which wipe out insects, drastically illustrated by the recent range-wide population collapse in the Yellow-breasted Bunting (Emberiza aureola).
In the mid-1990s, the observed decline of the Yellow-breasted Bunting Emberiza aureola in Hokkaido, Japan alerted conservationists that another super-abundant species might be in trouble. Now we know it has suffered a huge decline, possibly as much as 95 percent of its population, in the span of just two to three decades.
Use of glyphosate-based herbicides (GBHs) increased ∼100-fold from 1974 to 2014. Additional increases are expected due to widespread emergence of glyphosateresistant weeds, increased application of GBHs, and preharvest uses of GBHs as desiccants. Current safety assessments rely heavily on studies conducted over 30 years ago. We have considered information on GBH use, exposures, mechanisms of action, toxicity and epidemiology. Human exposures to glyphosate are rising, and a number of in vitro and in vivo studies challenge the basis for the current safety assessment of glyphosate and GBHs.
Few studies have quantified the relative reproductive success of passerines in urban habitats. I studied food availability and reproductive success of barn swallows Hirundo rustica in two urban habitats during 2012–2015. Barn swallows breeding in the town center experienced lower insect densities than those in the town periphery.
Agriculture Canada scientist Jeff Skevington, who works with the Canadian National Collection of Insects, says the country has lost a significant amount of its insect biodiversity in recent years based on the results of annual collection samples. That means a lot of the insects at the bottom of our food chain are dying out, which could have an unexpected, but noticeable impact on the lives of humans.
The research, published in the journal Insect Conservation and Diversity, involved taking recordings at four sites across East Anglia, nine times a year over an 11-year period from 2006-2016. Led by Dr Peter Brown of Anglia Ruskin University, who worked alongside Dr Helen Roy of the Centre for Ecology and Hydrology, the research found that the proportion of native ladybirds recorded at the sites (two lime tree sites, one pine tree site and one nettle site) declined from 99.8% in 2006 to 30.7% in 2016.
In his book, Dutch toxicologist Henk Tennekes (2010) makes the case that the contamination of surface water by neonicotinoids is so widespread in the Netherlands (and possibly elsewhere in Europe), that loss of insect biomass on a continental scale is behind many of the widespread declines that are being seen, be they of marsh birds, heath or meadow birds or even coastal species. This suggests that we should be looking at possible links between neonicotinoid insecticides and birds, not on a farm scale, but in the context of whole watersheds and regions.