The Northern Harrier (Circus cyaneus) is a hawk found in many habitats including farmland, marshes, bogs, and swamps. They are found throughout the Northern Hemisphere in places such as the US, Canada and the UK. Their main prey, constituting 95% of their diet, is small mammals though they will take small birds and amphibians. Due to their large range the IUCN lists them as "Least Concern", but they are highly endangered in England due to illegal poaching; there are as few as 4 breeding pairs left there. A reliable way to identify they is their white rump patch. This is especially helpful as the American subspecies is almost entirely brown.
We also saw an Osprey (Pandion haliaetus), another raptor. Ospreys are mostly fish eaters and are thus common around lakes and estuaries.
There were a large number of Northern Pintail (Anas acuta) ducks in the estuary. The males are easy to identify due to their long upright tail feathers and well defined head markings. The females are a bit harder to identify especially when grouped with other female ducks such as mallards and wigeons.
The Grey Flycatcher (Empidonax wrightii) was a new bird for my dad and me. As its name suggests it is insectivorous. This was not the easiest bird to identify as it was fairly far away and is about 6 inches long. The distinguishing mark is its two-tone beak- black on the top and orange/pink on the bottom.