Conserve Wildlife Blog

Posts Tagged ‘salamander’

Morning After Migration

Wednesday, March 13th, 2013

POST #2 ON THE 2013 AMPHIBIAN MIGRATION

by MacKenzie Hall, Amphibian Crossing Project Coordinator

 

The past week has been like a wild trip through biomes and time zones.  A half-foot of wet snow buried NJ on Friday, but it didn’t stand a chance against a  sunny weekend above 50˚F and the valiant arrival of Daylight Savings Time.  Bam!  Spring.  Suddenly birds were singing, crocuses were blooming, and salamanders were stretching their hamstrings for the journey ahead.

Throughout the day on Monday (March 11) a long wall of rain crept eastward across the US.  It couldn’t possibly miss NJ, and the temperature would hold around 50˚F overnight – excellent predictors for a migration.  The question was when the rain would hit and whether a rainfall starting very early in the morning would trigger many amphibians to move.  There seem to be almost unlimited permutations for how the important factors of ground thaw, temperature, rainfall, date, and time of night can converge, and after almost 10 years with the Amphibian Crossing Project I still learn new and surprising things. 

 

Snapshot of a Jefferson salamander being helped across the road.

Snapshot of a Jefferson salamander being helped across the road.

A handful of us chose to wait out the rain at one of our big road-crossing sites in Byram (Sussex Co.).  At least 3 hours before the rain even started, someone noticed a salamander crossing the dry road.  We spread out to cover more ground and kept counting.  By the time the first raindrops hit we had already tallied (and ferried) 190 salamanders and 20 frogs across the asphalt threshold dividing their forest habitat from the breeding pool below.  We were all pretty surprised and excited by what we were seeing.

The rain came around 2:30 am, and in the 4 hours before dawn the road was swimming with frogs and salamanders.  We did our best to keep up with the count, and the rescue, especially as vehicle traffic picked up toward dawn.  Eight cars per hour around 3:00 am, then 10 cars per hour, then 26.  By 6:15 it was hard for the last of us – Bob Hamilton and I – to keep our feet on the pavement as the vehicle count crested 100 per hour.  We also started to lose the battle against roadkill – as many animals were getting hit as we could save.  Luckily it was just a short period, and at dawn the migration would pause.   Our totals for that night:  1,119 salamanders and frogs, 954 of which made it to their destination!

Our “scouts” all across northern & central NJ had similar reports.  A big migration had happened before dawn, and there was some roadkill as evidence.  But you can listen for a happier kind of evidence – the honking and peeping of those who made it to their pool.  The harbingers of spring are arriving.

Amphibians on the March – in February!

Tuesday, March 6th, 2012

2012 MIGRATION SEASON BEGINS

by MacKenzie Hall, Biologist

Jefferson salamander - Bob Hamilton

A Jefferson salamander gets an early start on spring (Feb 24). Photo by Bob Hamilton

After the wimpy winter (which I quite enjoyed), we knew the amphibian migration could start a little earlier than normal this season.  The ground has been thawed since mid-February across most of NJ, leaving only a reasonably warm nighttime rain to propel frogs and salamanders into their annual breeding frenzy.

And in an oddly symbiotic way, their frenzy becomes ours as well.  This year, the Amphibian Crossing Project covers 6 road rescue sites in Warren, Sussex, and Passaic Counties – more than we’ve ever done before – and includes monitoring at a number of amphibian road-crossings in the Sourland Mountains region.  More than 130 trained volunteers are part of the migration survey, which aims to 1) help amphibians survive the dangerous cross-road journey to their breeding pools, and 2) collect data to find out which sites are most important and which populations are most threatened by traffic.  With all the new sites, new helpers, and big plans for the data we collect this year (stay tuned…), a lot is riding on the weather.  We and our scouts have been out in every little nighttime rainfall over the past month that’s been anywhere near 40 degrees.

Gene & Ginger

New volunteers Gene & Ginger Martel show that they're ready for migration! Photo by Ginger Martel

My first salamander of the season came out of the woods at 2:00 am on February 24th at a crossing in southern Sussex County, as light rain turned to snow in 37 degree air.  Aside from the three bulky humans watching him labor across the road, this Jefferson salamander had a quiet and uneventful trip.  No cars passed through; the only thing coming down on his cool skin was the occasional snowflake.  If you’re a slow, small amphibian, a middle-of-the-night migration is the way to go.  Your chance of survival is slim in the earlier evening’s traffic.

The nights of February 24th, 29th, and March 2nd were also rainy and just warm enough to draw some eager amphibians to the surface.   Jefferson salamanders are famously cold-hardy and have made a big push to their pools.  Spotted salamanders, wood frogs, and even a few spring peepers have taken advantage of the early thaw as well.  Peak migration is still ahead of us in northern NJ, though, so we’ll continue watching the weather and waiting for our next night out in the rain.

Spotted female

A large female spotted salamander, heavy with eggs, gets help crossing a Hunterdon County road (Feb 29). Photo by MacKenzie Hall