Black-headed x Ring-billed Gull (hybrid)
Hybrid Chroicocephalus ridibundus x Larus delawarensis
Black-headed x Ring-billed Gull (hybrid): https://marylandbiodiversity.com/species/17301
Synonyms
BHGU x RBGU
Chroicocephalus ridibundus x Larus delawarensis
