Why have these rodents turned completely green?

In recent news, large native rodents called capybaras in a lake in northeastern Argentina near Uruguay have been spotted with an unusual green color. This intriguing phenomenon is attributed to cyanobacteria, which are commonly found in water bodies worldwide.

The curious case of the green capybaras

These large, semi-aquatic rodents are native to South America and are the largest living rodents on Earth, weighing up to 145 pounds. Capybaras are known for their social behavior and adaptability to various habitats, including swamps, forests, and marshes. However, what has caught the attention of researchers and environmentalists alike is the sudden change in their fur color from brown to a vibrant shade of green.

This transformation is not a natural occurrence but rather a consequence of their interaction with cyanobacteria, which are microscopic organisms that can produce toxic compounds harmful to both humans and animals. Cyanobacteria thrive in warm, nutrient-rich waters and can form dense blooms that cause water discoloration – also known as algal blooms.

What causes cyanobacterial growth?

• Increased nutrient levels: The primary cause of cyanobacterial growth is an excess of nutrients like phosphorus and nitrogen in the water. These nutrients can come from agricultural runoff, sewage discharge, or even natural processes like plant decomposition.
• Warm temperatures: Cyanobacteria prefer warmer conditions; hence they tend to proliferate during summer months or in areas where global warming has increased water temperatures.
• Calm waters: These microorganisms thrive in calm waters with little turbulence. Lakes and ponds are therefore more susceptible to cyanobacterial blooms as compared to rivers and streams.

The impact of cyanobacteria on capybaras and the environment

When capybaras come into contact with water containing high concentrations of cyanobacteria, their fur absorbs the green pigments produced by these microorganisms. While this color change might not have any immediate detrimental effects on the rodents, prolonged exposure to cyanotoxins can lead to health issues such as liver damage or even death.

Furthermore, cyanobacterial blooms can have a significant impact on the aquatic ecosystem. They reduce light penetration in the water, affecting the growth of other photosynthetic organisms. When cyanobacteria die and decompose, they consume oxygen in the process, leading to oxygen depletion in the water body. This can result in fish kills and harm other aquatic life forms.

How can we prevent and control cyanobacterial blooms?

In order to protect both humans and animals from the harmful effects of cyanobacteria, it is essential to implement preventive measures and control strategies. Some of these include:

• Monitoring nutrient levels: Regular monitoring of nutrient levels in water bodies can help identify potential sources of nutrient pollution and enable timely intervention.
• Reducing nutrient input: Implementing best management practices for agriculture, wastewater treatment, and stormwater management can help minimize nutrient input into water bodies.
• Physical removal: In some cases, manual or mechanical removal of cyanobacterial biomass may be necessary to mitigate its harmful effects on aquatic life.

By taking these steps, we can work towards preserving our environment and safeguarding the health of both humans and animals like capybaras that are affected by this phenomenon.