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Since the 1980s, there has been a worldwide decline in the population of amphibians – frogs, toads and salamanders. For a while, biologists were skeptical that these declines were anything more than natural variations. However, study after study has revealed that the amphibian decline is a real and severe threat to biodiversity. Roughly half of amphibian species have decreasing populations, a third are globally threatened, and almost 500 species are critically endangered. The causes for this dramatic die-off appear to be varied. Some studies have concluded that farm pesticides are a major culprit. Other studies have identified a type of chytrid fungus that causes skin infections as a major contributor to the worldwide decline.

Box turtles are amazing little animals. The word turtle usually equates to a reptile that primarily lives in water. However, box turtles spend the majority or all of their life on land. Being territorial, box turtles live in a designated area that provides them with food, water, shelter and places to raise young. They feed on a multitude of items, including worms, insects, fruits, berries, mushrooms, plants, fish, small animals and even occasionally carrion. Two or three decades ago, box turtles used to be fairly commonly observed in the suburbs and rural areas around Montgomery County, especially after a heavy spring or summer rain. Seeing three or four box turtles in a day was commonplace. Now, if you observe three or four a year you are lucky.

More than 200,000 wood frog tadpoles died within 21 hours last year at a pond in Nat Wheelwright’s backyard in Brunswick, in what may be the largest and fastest mass death of tadpoles ever reported. The Bowdoin College biology professor is trying to find out why. This year, the wood frogs came back to Nat Wheelwright's pond, but there were no 1-year-old frogs breeding and the number of tadpoles was lower than previous years. “It was something I had never seen before,” said Wheelwright, who has studied the frogs in his yard for 28 years. “It was like a nuclear bomb went off.” The tadpoles were covered with red hemorrhages and tested positive for ranavirus, which likely caused the die-off, said Wheelwright.

The world's soaring human population has slashed the numbers of creepy crawlies a study has found. However, researchers say the demise of slugs, spiders and worms is not good news for us humans and could spark an explosion in pests. The study, published in the journal Science, revealed that as the human population has doubled over the last 35 years to now stand at more than seven billion, invertebrate numbers have fallen by nearly half over the same period. Experts fear this could have an effect on ecosystems as insects, spiders, crustaceans slug and worms play an important role in pollinating crops, pest control, decomposition and ensuring soil remains packed with nutrients, as well as water filtration. In the UK these two factors caused a massive reduction in the number of beetles, butterflies, bees and wasps, a 30-60 percent fall over 40 years, according to the study.

From white-winged scoters and surf scoters to long-tailed ducks, murres, loons and some seagulls, the number of everyday marine birds here has plummeted dramatically in recent decades. The reasons are often complex, but for many the loss of forage fish like herring might hold a clue. Bird surveys done by plane are tracking a significant ecological shift — a major decline in once-abundant marine birds. Scoters are down more than 75 percent from what they were in the late 1970s. Murres have dropped even more. Western grebes have mostly vanished, falling from several hundred thousand birds to about 20,000. Several new studies link many dwindling marine bird populations to what they eat — especially herring, anchovies, sand lance and surf smelt, the tiny swimmers often dubbed forage fish.