Wild poultry, which tend to fly a lot more, tend to only contain “dark” meat, which contains a higher amount of myoglobin due to the muscles needing more oxygen from frequent, continual usage.

它们的肌肉里含有极多的肌红蛋白，因为飞行中肌肉的频繁连续工作需要更多氧气。

youdao

Seventy percent of an average turkey is white meat while thirty percent is dark meat.

VOA: special.2010.05.28

In general, Americans like the white meat better than the dark meat.

VOA: special.2010.05.28

Goose is all dark meat, with an intense flavor more often compared to beef than chicken.

NPR: How to Cook Your Goose

The wild birds are smaller, firmer, and have a rich, intense flavor since they are mostly dark meat.

NPR: Wild Things Thanksgiving

You can use breast meat, but the more flavorful dark meat will do better justice to your secret sauce.

NPR: Dinner's Secret Weapon: The Make-Ahead Marinade