Coral reefs are a necessary part of sea life and support it by providing shelter and habitat to various organisms. They also supply and recycle nutrients as well as enable a fish population to boom, along with other species, for a healthy and diverse ecosystem.

However, the rise in average water temperatures due to climate change has resulted in more frequent and extended “coral bleaching(珊瑚白化)” events that damage their health, causing fish and other sea species to abandon them.

In order to repair this delicate ecosystem, scientists from the UK and Australia conducted a study that involved using speakers underwater near damaged coral reefs to make them sound healthy and attract fish, potentially starting the natural recovery press of coral reefs and their dependent life forms.

The location for this experiment was the Great Barrier Reef in the Coral Sea, found alongside the east coast of Queensland Australia, which is famous to have the largest coral reef system in the world that’s 2, 300 kilometers long and covers an area of nearly 344, 400 square kilometers. By using loudspeakers to reproduce such sounds, areas of dead coral reefs were found to attract twice as many fish, compared to places where no sounds were played. These returning fish could help in the recovery of this ecosystem by giving those areas of coral a chance of new life.

“Fish are important for coral reefs to function as healthy ecosystems. Increasing fish populations in this way could help to start natural recovery process, reducing the damage we’re seeing on many coral reefs around the world. Of course, attracting fish to a dead reef won’t bring it back to life automatically, but the recovery process relies on fish that clean the reef to make space for corals to regrow.” said Mark Meekan.

Outdoor lighting in general poses a deadly threat to insects. That’s according to a study published online in November 2019 in the journal Biological Conservation, entitled “Light Pollution Is a Driver of Insect Declines”.

The article notes that sudden drops in insect numbers around the world have happened over the past couple of decades in what amounts to an insect destruction. The blame is usually assigned to “habitat loss, chemical pollution, invasive species, and climate change”. But the authors argue that the forces of lightness have not gotten their due.

A longtime preference among ecologists for studying daytime phenomena, and a preference for sleeping at night has led insect conservationists to overlook another widespread habitat disturbance, pollutant, and method of insect control: artificial light at night(ALAN).

ALAN’s influence occurs through its interference with the development, movement, foraging, and reproductive success of diverse insect species. Another factor is light’s positive effect on insectivore predation. That is, birds, bats, amphibians and arachnids aren’t stupid-if a lot of insects start swirling around lights in the night, predators will also show up.

Sadly, ALAN increases sharply after Thanksgiving, as many people add festive illumination(照明) to the exterior of their houses to celebrate the approach of Christmas. Many neighborhoods have a particular house that embraces the spirit of the season in such an outsized way as to produce a radiant haze perhaps visible to hunters in other star systems.

The task then must be to lessen the ecological consequences of ALAN on insects while still maintaining sufficient levels of nighttime illumination for human safety and enjoyment.

“Monochromatic LEDs can be engineered to produce light of any desired spectral composition,” the investigators write. “Therefore, once we know the specific wavelength affinities of insects, we can in theory design lights with minimal output in the wavelengths that most affect insect fitness.”

Turning some of the lights off might also help. In many cases, it is far easier, quicker, and cheaper to block, dim, or turn off a light source than it is to find the particular bulb type or narrow bandpass filter(滤波器) that makes its emissions visible to humans alone. Help end the war on insects. It is better to blow out one candle than to curse the planet.