Water Closet for April 24, 2017
“The netters, ages from 2 to 84 years, didn’t find salamander or wood frog egg masses as the old timers had expected.”
On Sunday afternoon, April 9th, Middleton Stream Teamers and guests went forth with nets and plastic bowls to look for creatures in rain-melted iceless pools west of Middleton Pond near the North Reading line. We could have gone almost anywhere in the woods; vernal pools are found in much of the town and beyond. We’d been hearing the low crackles of wood frogs and high pitched peeps of peepers for a week and expected to find egg masses of wood frogs and those of silent yellow-spotted salamanders in long familiar pools.
Even after a week of rain, with nights and days of temperatures in the 30s to 50s, the group of fifty didn’t find either. They scooped up many beautiful, half-inch long fairy shrimp, denizens of these fishless pools. Fish can’t sustain populations in pools that dry up most summers and have no outgoing or incoming perennial streams. The transparent big-eyed, red-orange, belly up swimming beauties are very vulnerable. In pools without fish, salamander larvae and wood frog tadpoles can survive long enough to metamorphose into little adults if there is water present long enough. Then on new legs they retreat to the damp forest duff and soils their parents came from. It is thought parents return each year to the pools in which they were conceived, drawn for a so-called “big night” of reproduction in pools of exposed high ground water.
The netters, ages from 2 to 84 years, didn’t find salamander or wood frog egg masses as the old timers had expected. It was the right time of year, the pools were full and the previous week’s temperatures and humidity had been favorable. The old Stream Teamer, who roams around the woods in all weathers and seasons, often passing vernal pools, wonders if February’s strange long period of warmth might be the reason. After extended thaws in January and February the pools were often ice free or nearly so except for surface skins in the morning after freezing nights. Under thin snow and last fall’s leaves the soils were not frozen as in most winters. In late February we were hearing spring peepers, buds were growing and pussy willows were being gathered. Spring, strangely a whole month ahead of time, appeared to be here. Had the salamanders on warm nights left the duff covering their woodland soils and visited the pools in February? Did the dark eggs and embryos absorbing the sun’s warmth hatch early into larvae (tadpoles) that survived under March’s ice? Did eggs remain dormant through cold March, dormant in ice or in 32 F degree water? We found no signs of egg masses. On February 26 Ipswich River water testers at Thunder Bridge measured the water temperature at 41 F, a month later at the same spot it had dropped to 35 F. In normal years these numbers would be reversed.
Reversals make for interesting guesses, scientists call hypotheses, which lead to more questions, studies, and experiments. We in the Stream Team don’t usually get much beyond the observation and guessing stages. This year we’ll ask naturalists more in the know what they think and also continue trips to the pools for clues. Perhaps there just haven’t been reproductive visits by spotted salamanders yet; and the wood frogs have just not conjugated again as they may have in warm February. The sounds of peepers, tree frogs, and wood frogs and the presence of fairy shrimp seem to belie this.
How essential these woodland vernal pools are to animals that have gotten their start in them for millions of years. The old Stream Teamer guesses there may be 200 vernal pools in Middleton alone. The Wetland Protection Act often hailed here keeps people with bulldozers from filling these spring nurseries once deemed by farmers and then developers as just in the way puddles. Now our conservation commissions watch out for them and ask for undisturbed buffers out from their edges.
If you’d like to know more about these valuable pools contact the Middleton Steam Team or your town’s Conservation Commission. There is a book we much value that guides us amateurs. A Field Guide to the animals of Vernal Pools by Leo P. Kenney and Matthew R. Burne, published by the Natural Heritage and Endangered Species Program, is richly illustrated with colored photos and has good basic descriptions of their habits and life cycles. Contact the Vernal Pool Association if you’d like to obtain one. While you are waiting for your guide, guide yourselves to bodies of water nearby that declare themselves each spring with over knee deep water and animal sounds. Bring a fine net and gently sweep along the bottom debris. Our temporary puddles are full of life. If you don’t find the species mentioned above you’ll usually find many insect larvae, worms, tiny snails, little clams, crustaceans . . . the list goes on. _______________________________________________________________________________
WATER RESOURCE AND CONSERVATION INFORMATION
FOR MIDDLETON, BOXFORD AND TOPSFIELD`
|Precipitation Data* for Month of:||Jan||Feb||Mar||April|
|30 Year Normal (1981 – 2010) Inches||3.40||3.25||4.65||4.53|
|2017 Central Watershed Actual||4.02||3.46||2.89||4.9**as of April 13|
Ipswich R. Flow Rate (S. Middleton USGS Gage) in Cubic Feet/ Second (CFS):
For April 13, 2017 Normal . . . 124 CFS Current Rate . . . 194 CFS
*Danvers Water Filtration Plant, Lake Street, Middleton is the source for actual precipitation data thru March.
** Middleton Stream Team is the source of actual precipitation data for April..
Normals data is from the National Climatic Data Center.
THE WATER CLOSET is provided by the Middleton Stream Team: www.middletonstreamteam.org or <MSTMiddletonMA@gmail.com> or (978) 777-4584