CONROE, Texas (AP) — A sharp fingernail-size shellfish pest that’s been advancing steadily across much of the eastern and central parts of the country now has a foothold in Texas where it’s changing the way recreational users are playing with their water toys.

New regulations that took effect statewide this week are aimed at easing the spread of the invasive zebra mussels species in Texas rivers and lakes. The mussels attach themselves to almost anything in the water and then multiply, upsetting the ecology of the lake or river.