Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of oil and gas explorer Gran Tierra Energy (AMEX: GTE) are down 11% this morning on many times the average trading volume.

So what: The Canadian firm just disclosed a disappointing lack of hydrocarbons in its Peruvian Kanatari-1 reserve, despite the presence of a "spectacular reservoir-quality sandstone section" that seems ideal for production. There's nothing but water there, and Kanatari-1 will be plugged and abandoned.

Now what: On the other hand, Gran Tierra found free-flowing oil in its Moqueta-4 well in Colombia and is building a pipeline there to support drilling by April. Still, that's the outcome you want from the majority of your exploratory wells, so the bad news overtakes the good today. Former Fool contributor Toby Shute found Gran Tierra "interesting" in 2009, but only if those Peruvian reserves were proven full of black gold.

Interested in more info on Gran Tierra Energy? Add it to your watchlist.

Fool contributor Anders Bylund holds no position in any of the companies discussed here. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool is investors writing for investors.