Snake on a bridge

My friend Jeri told me about encountering a bothriechis schlegelii, known commonly as the eyelash viper, while crossing a suspended wire bridge in a rainforest in Costa Rica.

She and her husband were with a guide when they were about to cross the bridge. Their guide matter-of-factly explained that there was an eyelash viper who liked to hang out on one of the supporting wires about halfway across the bridge.

Eyelash vipers have strong prehensile tails and are ambush predators. Basically they like to wait patients for unsuspecting prey. Their menu includes small rodents, frogs, lizards and birds. And so it was that there was an eyelash viper wrapped around a wire halfway across a bridge in the rainforest waiting for something to eat.

Their guide was pragmatic. He stressed that if they could quietly slide by the snake they should be fine -- but just in case their presence aggravated the viper they should move their backpacks to their chests to provide a bit of protection from any potential viper strikes.

And so Jeri and her husband and their guide quietly and quickly slid right by the eyelash viper on the bridge. Then they laughed quietly to themselves. "In for a penny, in for a pound,' said Jeri as she described the moment they came face to face with a snake whose bite can be very painful and potentially deadly.

Dianne and I are just back from a two-week vacation in Costa Rica. During our visit we went on many adventures which involved getting up close and personal with the flora and fauna of the country. On one such outing we had decided to hike through a nature refuge that includes several suspended bridges and a trail through the rainforest.

We opted for a self-guided visit to the refuge and when we arrived a torrential tropical downpour was underway. It's always interesting when a visit to a nature refuge includes signing a waiver in which you acknowledge you are aware of the risks involved due to the wildlife.

Other visitors were streaming into the base station as we plunged, literally, into the rainfall and started our hike. We had been briefed on the potential presence of a fer-de-lance snake along a certain part of the trail -- right between two suspension bridges.

The terciopelo (bothrops asper) or fer-de-lance is a large pit viper. Known to be aggressive the terciopelo is responsible for the vast majority of snakebites in Costa Rica. The fer-de-lance is potentially deadly. It the bite doesn't kill you, it is likely to cause necrosis and multiple organ failure. It is a nasty piece of business and has earned the awful nickname as the Costa Rican landmine.

As we made our way along the trail, there was a sign reminding us to be wary of snakes. Dianne noticed the man standing in the rain first. "Is he holding a shotgun ?" she asked. As we got closer we realized he was holding a long machete in one hand as he stood by the side of the trail.

"There's a fer-de-lance snake here," he said calmly in Spanish. We looked at the big viper coiled tightly by the trail as we quietly and quickly made our way past. It wasn't time for a selfie with the snake. As we made our way further along the trail we remembered Jeri's story about the eyelash viper on the bridge.

Rain seems to be a calling card for creatures to come out and explore. And while we didn't encounter any more serpents, we were treated to a very showy display by green and black - almost neon-coloured - frogs. Dianne leaned in to get some great close-up shots.

As it turns out, these were green and black poison dart frogs (dendrobates auratus). As in most poison dart frogs, the vivid coloration and patterns of the Green and Black Poison Dart Frogs serves a warning to would-be predators that eating them may be harmful to the predator’s health. Their alkaloid toxins are secreted through canals in their skin and is expelled if the frog is touched or bitten.

I called Jeri yesterday to tell her our story of the snake on the trail and how we had laughed, albeit nervously, as we remembered her own story of the snake on the bridge. It's interesting how when we're on vacation and fully-immersed in another environment, we adapt our sensibilities. We were aware of the risks and opted to explore and observe - as safely as we could under the circumstances.

I consider myself very privileged to have witnessed a slice of life while on a walkabout in a rainforest. It wasn't, as some people lamented in their reviews, like going to the zoo. There was no guarantee we'd be able to observe any animals at all. As we talked with other visitors we realized they hadn't encountered the fer-de-lance by the side of the trail. We were lucky to have, safely, crossed paths with one of the most dangerous snakes in Costa Rica and to have seen several poison dart frogs.

It makes for one helluva story.