Note: It’s possible that the last two images in this series were baited. Hopefully some will find this post useful in helping them to appreciate these magnificent birds even more. If the weather and many other factors cooperate, the month of February often provides some fantastic opportunities for eagle watching in northern Utah, especially at some of the wetlands around the Great Salt Lake like Farmington Bay NWR. Here you can compare three plumage stages of Bald Eagles in one photo.ġ/800, f/11, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called inġ/1000, f/11, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called inĪn adult on the right, a first year bird on the left and an intermediate juvenile in the middle with some interesting mottling. This bird has fish blood on its beak and if you look closely you’ll see that it has a “blown eye” (misshapen pupil, possibly due to injury).ġ/1600, f/8, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called in Both head and tail are now completely white with overall dark brown plumage elsewhere. The tail is now bright white but there remains some dark flecking on the head.Ī fully mature adult. This bird is very nearly in full adult plumage. The tail now lacks the dark terminal band and the beak is nearly completely yellow. Some birds at this stage (like this one) exhibit a few secondary flight feathers that are longer than the rest at the trailing edge of the wing.ġ/640, 7.1, ISO 800, 500 f/4, 1.4 tc, not baited, set up or called inīy the fourth year (though there’s much variation) the head is mostly white with some dark flecking around the eye and forehead near the cere. The beak becomes more yellow (though not as bright as in the adult). The eye is becoming more yellow and the eye-stripe quite distinctive.ġ/1600, f/8, ISO 500, 500 f/4, not baited, set up or called in The beak is less dark and as the head becomes lighter generally it leaves a darker “eye stripe”.ġ/1000, f/8, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called in The iris is beginning its transformation to yellow and there’s also some yellow at the base of the beak.ġ/1250, f/7.1, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called inĪs plumage stages develop through the second and third years the tail becomes whiter with a dark terminal band and more white appears elsewhere. There is more mottling and the beak and cere are becoming less dark.ġ/1600, f/6.3, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called in Plumage after the first year becomes increasingly variable. This stage is often confused with the Golden Eagle (Golden Eagles have feathered lower legs or tarsi while Bald Eagles do not).ġ/3200, f/8, ISO 500, 500 f/4, not baited, set up or called in The warm, early morning light gives it a bit of a golden glow. Both eye and beak are very dark.ġ/2000, f/6.3, ISO 500, 500 f/4, 1.4 tc, not baited, set up or called inġ/800, f/8, ISO 500, 500 f/4, natural light, not baited, set up or called inĪ side view of the same bird as in the previous image. Notice that the plumage is dark brown throughout, though they may have some white or pale mottling at this stage – especially on the underparts. This very young bird is barely fledged and was still hanging around its nest in sw Montana. The adult Bald Eagle is unmistakable with its distinctive bright white head and tail contrasting with the dark brown body and wings.ġ/200, f/6.3, ISO 800, 500 f/4, 1.4 tc, not baited, set up or called inīut juveniles present very differently than adults, especially in the early stages of development. Eyes gradually change from dark brown to yellow while the beak goes from blackish-gray to yellow.ġ/4000, f/8, ISO 500, 500 f/4, not baited, set up or called in Plumage stages are highly variable, depending on molt sequence, age and timing so other factors like iris and beak color are also taken into account when estimating age. Many of these younger birds are mistakenly identified as Golden Eagles by the general public.Įagles that have not reached the adult stage are referred to as immature, juveniles or sub-adults. As we go into prime “eagle watching” season here in northern Utah I thought it might be timely to present a guide that would be helpful in aging Bald Eagles as they progress through the 5-6 year process of becoming adults.
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