Monthly Archives: June 2010
Wetland cows
The cows pictured here came to investigate the noise I made while searching for tadpoles. They stared impatiently and I sifted through samples, waiting until I left to continue their daily grazing.
Mimosa pigra
| A spiny Fabaceae, Mimosa pigra inhabits the margins of wetlands and is touch-sensitive. It’s flowers form a small, ball-like inflorescence and develop into seed-filled pods when fruiting. Among other characteristics, M. pigra is told from M. dormiens, another common spiny plant at wetland margins, in having curved spines along leaf rachis and more erect stems. |  |
More Thalia herbivores
Rain rolls into Lazaro
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Convolvulaceae
| I never got the chance to photograph this wetland plant before – Ipomoea carnea. It occurs in small, thick, patches, which emerge in relatively shallow areas, and has a thick, woody stem, particularly at the base. |  |
Tadpole catching equipment
| Seining is ineffective because of the thick vegetation, so sweeping with a D-frame net and sorting with a colander is the only option. So far, this method hasn’t produced enough catch… |  |
A wetland view
One of the few places with open water.
A Brown Tower
Although not in Palo Verde, I’ve been meaning to post this photo of the Observatory in Providence.
Bird Tower
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I climbed the broken down bird tower in the center of the wetland yesterday in search of tadpoles. I haven’t had luck on my own, but Mahmood volunteered to assist me. Another option may be to hormonally induce adult frogs to release their eggs/sperm in the lab. However, that only solves the problem of obtaining tadpoles to manipulate, it doesn’t help in estimating natural densities, which is important to know if I want to argue an important role of tadpoles in decomposition. The wetland is significantly deeper this year than it was last, at least for the middle of June. What’s more, the vegetation is thicker – the Neptunia has even started to flower! The tower, although flimsy, gave me a pretty good view of how solid the vegetative cover is – maybe 5% of the wetland is open and can be seined for tadpoles. Of the points I’ve tried, I’ve seen zero tadpoles…. By the way, sorry for not taking a photo from the top of the tower – I trusted it with my life, but not my camera. |
