Declining Megafauna species

Why in news?

A research published in the journal Conservation Letters showed that at least 200 species of “megafauna’ are decreasing in number.

What is the background?

• The researchers were part of an international collaboration that built a list of megafauna based on body size and taxonomy.
• The species qualified for the list were species unusually large in comparison to other species in the same class.
• The mass thresholds were 100 kg for mammals, ray-finned fish and cartilaginous fish and 40 kg for amphibians, birds and reptiles.
• Megafauna species are more threatened and have a higher percentage of decreasing populations than all the rest of the vertebrate species together.

What does the research reveal?

• Over the past 500 years, humans’ ability to kill wildlife at a safe distance has become highly refined.
• Hence, 2% of megafauna species have gone extinct in the period.
• Humans’ meat-eating habits may be pushing at least 150 species of the planet’s largest animals towards the threat of extinction.
• e.g Chinese giant salamander is one of only three living species in an amphibian family that traces back 170 million years.
• Considered a delicacy in Asia, it's under siege by hunting, development and pollution.
• Nine megafauna species have either gone extinct overall, or gone extinct in all wild habitats, in the past 250 years.
• Direct harvest for human consumption of meat or body parts is the biggest danger to nearly all of the large species with threat data available.
• Thus, minimising the direct killing of these vertebrate animals is an important conservation tactic.
• Users of Asian traditional medicine also exert heavy tolls on the largest species through the consumption of various body parts.
• This might save many of these iconic species as well as all of the contributions they make to their ecosystems.
• In addition to intentional harvesting, a lot of land animals get accidentally caught in snares and traps, and the same is true of gillnets, trawls and longlines in aquatic systems, along with their habitat degradation.
• When taken together, these threats can have major negative cumulative effects on vertebrate species.
• In the future, 70% will experience further population declines and 60% of the species could become extinct or very rare.
• The report warned that preserving the remaining megafauna is going to be difficult and complicated.
• There will be economic arguments against it, as well as cultural and social obstacles.
• But if we don't consider, critique and adjust our behaviours, our heightened abilities as hunters may lead us to consume much of the last of the Earth's megafauna.

What does the EAT-Lancet report reveal on human diet consumption?

• Transforming to healthy diets by 2050 will require drastic changes.
• Global consumption of healthy foods, such as fruits and vegetables, will need to double, while overconsumption of foods like added sugars and red meat will need to be more than halved.
• At the same time, it will be equally important to take a differentiated approach for healthy and sustainable diets in developing countries and for poor populations.
• For many developing countries and the poor, under-nutrition and access to healthy foods remain persistent challenges.
• Small amounts of animal-sourced foods (ASFs) (like dairy, eggs, fish or chicken) for young children and women during pregnancy and lactation are crucial for nutrition and health, especially in poor populations.
• There is a strong association between reduction in stunting and ASF consumption.
• Hence, healthy and sustainable diets may look different from country to country and animal sourced foods serve as an inevitable part to tackle malnutrition among poor populations.

Source: Business Line