Category Archives: Amphibians
If you love amphibians and missed the breeding season on the west side of the state, take a trek over the Cascades and you’ll find more breeding! With higher elevation and different rain patterns, the amphibians on the east side breed much later (in actual Spring!) than their west side counter parts that already did their thing last February.
The Oregon spotted frog (Rana pretiosa) is a mostly aquatic species that used to occupy the Willamette Valley and the Cascades. In 1993, USFWS designated it a threatened species, but did not list it due to other higher priority species needs taking precedence (down side of being a wildlife biologist: prioritizing species’ lives). Last August, USFWS proposed to list the Oregon spotted frog as threatened. So, USFWS is gathering more data about them, and invited OPRD to survey a known breeding site along the Deschutes River at La Pine State Park. USFWS wants us to go look for awesome amphibians to help the species? Absolutely!
So last week I drove over to Bend and met up with Greg Cianella, our Natural Resource Specialist for the Eastern Region. He had arranged everything – kayaks, data sheets, GPS and maps – so all I had to do was get in the boat and start paddling.
In contrast to our other breeding frogs, Oregon spotted frogs breed in very shallow water – preferring it less than a foot deep. They like it still, shallow, and what a lot of us people consider “icky”. Breeding areas are often devoid of emergent vegetation where the sun can warm the water – and the eggs – quickly. The breeding season is very short, only about four weeks long. That means when it’s time to survey you get out there and do it!
They lay their eggs as large masses that float on the surface when fresh. The masses are about the size of an orange, and as they mature the mass gets more “fluffy” and swells in size.
While we were trying to get a nice shot, maneuvering kayaks around, Greg noticed something different laying on the bottom of the slough. We did some more maneuvering – the wind was determined to move us where we didn’t want to go – and managed to get a good look at the stuff. Long strings! Everywhere. Like really long shoe laces crisscrossing the muddy substrate. Yet MORE maneuvering, and I managed to carefully lift the mystery shoelaces up to see them. The sediment dusted off and revealed a beautiful string of delicate eggs.
All told, we found 30 spotted frog egg masses, the toad eggs, quite a few bufflehead, a slough of mallards, and sunshine on the water.
It was a good day to be a wildlife biologist!
It was a sunny day last Wednesday when our North Coast Steward and I took the NCC Silver 1 AmeriCorps team out for some training in wildlife surveys and marsh walking. Silver 1 is serving with Oregon State Parks on the central and north coasts for 10 weeks this winter. They are helping OPRD staff implement much needed restoration and research projects throughout our parks, focusing on the Beaver Creek State Natural Area. The team will survey areas of Beaver Marsh this late winter to count amphibian egg masses, which sounds pretty dull! But mincing around through a calm, cool marsh in highly stylish waders, surrounded by amazing birds, and looking through the water for egg mass treasures is a lot more fun than you might think!
They will find egg masses and document some habitat features in the area, like water depth and vegetation. OPRD (me) will then be able to compare to last year, and do it again next year, and as the years go by we will have an idea about what the amphibian population is up to in the marsh. Amphibians are often one of the first groups of species to respond to changes in the ecosystem, which makes them excellent indicators of ecosystem health.
We can already see a difference from last year – it seems that spring came early! There were already a lot of egg masses in the marsh, when last year about this same time there were only a handful. For OPRD this is important information so that we can plan restoration projects during times of the year that will have the least negative impact on our natural resources, like breeding amphibians! For the Americorps team, who works on lots of trail building and community projects, this is a unique opportunity to experience a completely different set of work challenges. Maybe we’ll make a wildlife biologist out of one of them!
Do you like slimy, cold, and adorable? I do! Frogs and salamanders abound in many of our State Parks, and late winter and early spring is one of the best times to find them. Amphibians are excellent indicators of ecosystem health, and tracking trends in their populations or productivity can help showcase changes in the environment before other species do.
Besides, who can resist these eyes?
Photo Credit: Sara Viernum
This past February OPRD’s wildlife program hosted surveys for lentic breeding amphibians at four of our parks. A “lentic breeding amphibian” is one that spends its adult life on the earth but lays its eggs in ponds or other still water places, like red-legged frogs (Rana aurora) and northwestern salamanders (Ambystoma gracile). With the help of interns from Oregon State University, we donned waders, datasheets, and the mighty Swamp Stick to set out in the wetlands, marsh, and ponds at Beaver Creek Natural Area, Bower’s Rock State Park, Champoeg State Park, and Wapato Access.
What, you might ask, is a Swamp Stick? Here I am with OPRD Natural Resource Specialist Katie Duzik, modeling the latest in amphibian tracking gear. The stick was craftily pieced together from PVC pipe, zipties, and a big spoon. It serves three functions: giving a nice white background to show what is in that dark water, a way to manipulate delicate amphibian egg masses without needing to touch them, and probably most important for staying dry, as a ground prodding stick to make sure there really is something solid in front of you!
Here you can see the bottom of the Swamp Stick, the nice big spoon, showing off some red-legged frog eggs. Handling egg masses could detach them from their anchoring vegetation, but sometimes you need to move them a bit to see what they are: Swamp Stick. The young frogs are in the “tailed” stage, where you can see them starting to develop a tadpole-like form.
Photo credit: Vanessa Blackstone
Here are some more fantastic pictures!
Pacific chorus frog egg mass. Photo Credit: Vanessa Blackstone
Long-toed salamander egg mass. Photo Credit: Vanessa Blackstone
Northwestern salamander egg mass. Photo Credit: Vanessa Blackstone
Now all the data is in a pile on my desk, waiting for analysis. Wait, I think I have a bird survey to go on… paperwork will have to wait for a rainy day!