NEW IBERIA, La. — Forty years ago, Mike Richard was looking for a way to reduce the amount of groundwater being used at his family’s nursery near New Iberia. He converted a cattle pasture into a series of ponds. “I needed an irrigation pond to treat the water for the nursery and to capture runoff, rainwater coming from the hillside,” Richard said. He had a second goal in mind when he designed the ponds. “I built islands on it because I wanted to have a habitat for the aquatic birds,” he said.