Amphibians are more vulnerable to extinction compared to reptiles, birds (aves), and mammals. There are several reasons for this.

1. Habitat Loss: Amphibians are highly dependent on freshwater habitats, such as ponds, lakes, and rivers, for breeding and development. However, these habitats are rapidly declining due to human activities like deforestation, urbanization, and pollution. As a result, many amphibian species are losing their breeding grounds and suitable habitats, increasing their vulnerability to extinction.

2. Sensitivity to Environmental Changes: Amphibians have very permeable skin, which makes them highly sensitive to changes in their environment. They are particularly susceptible to pollutants, pesticides, and climate change. Even slight shifts in temperature or water quality can have a significant impact on amphibian populations, leading to declines and potential extinctions.

3. Disease and Fungal Infections: Amphibians are prone to various diseases and fungal infections, such as chytridiomycosis caused by the fungus Batrachochytrium dendrobatidis (Bd). This disease has been implicated in the decline and extinction of numerous amphibian species worldwide. It affects their skin, impairs their ability to breathe and regulate water balance, and ultimately leads to death.

4. Reproductive Challenges: Amphibians have complex life cycles that often involve breeding in one habitat and living in another. This makes them more vulnerable to disruptions in their reproductive patterns. For example, if a breeding site dries up or is polluted, it can prevent successful reproduction and cause population declines.

5. Limited Mobility: Compared to reptiles, birds, and mammals, amphibians generally have limited mobility. Many species are highly dependent on specific habitats and cannot easily disperse to new areas if their current habitat becomes unsuitable. This lack of mobility restricts their ability to adapt to changing environments and increases their vulnerability to extinction.

6. Overexploitation and Illegal Trade: Some amphibians are targeted for their skin, meat, or use in traditional medicine. Overexploitation, combined with illegal trade, has put additional pressure on amphibian populations, pushing them closer to extinction.

Overall, the combination of habitat loss, sensitivity to environmental changes, disease susceptibility, reproductive challenges, limited mobility, and overexploitation makes amphibians more vulnerable to extinction compared to reptiles, birds, and mammals. Efforts to conserve and protect amphibians are crucial to prevent further declines and potential extinctions.

Amphibians, 33% of all vertebrates.