Rana virus out of control
In my wetland restoration project here in Upper Bucks County,PA, the rana virus is rampant. It has already killed box turtles and snakes that I found, and who knows how many I haven't found.
Also, the fatality rate on amphibian larvae, and to a lesser degree, adults, is tremendous. By my estimate to be nearly 90% of tadpoles. The ponds can be full of wood frog tadpoles starting in April, but come June, just as they're getting ready to morph into frogs, most of them disappear. They did not morph and move on to land, I paid close attention to their development, they disappeared just as they began forming back legs.
From what I can tell from my web research, there is really nothing that can be done to combat this virus. It seems to me that perhaps the green frog tadpoles, which take two warm seasons to morph, might be the main reservoir for this virus.
We can only hope, because of the high breeding rate of amphibians, that a immunity to the virus can be attained by survivors breeding with other survivors. But its certainly a different story for the slow breeding reptiles. Since the area is fenced protected because of the large deer pressure here, I'm going to try to secure the bottom so I can keep the local box turtles from reaching the ponds area. The virus can be very fast acting on reptiles. A few summers ago I saw a healthy looking box turtle escaping a scorching summer day by immersing itself in the pond. A week later I found it dead, with no apparent physical damage.
And I no longer see ANY salamanders under the rocks and logs where they previously plentiful.
Anybody have any thoughts or insights to this dreadful disease? I have a sick feeling that by maintaining these ponds I may be contributing to the problem.