Closeup of thick-billed weaver crushing seeds in its beak on a grassy field, South Africa

thickbilled weaver grosbeak weaver bird bill beak green grass chewing meal hungry birding bird watching wildlife south africa outdoor wild lawn garden avian conservation natural seed tour safari brown amblyospiza albifrons ecosystem feather male biodiversity park exotic tropical closeup 4k aviary birdlife pecking feeding african sighting encounter field defenceless vulnerable crushing