Led by Yellow-faced Honeyeaters, at its peak the migration can see 20,000 birds an hour pass low over the swamp and roadway at Pambalong. During the really big "pulses" several thousand birds can fly over within a couple of minutes and the really great thing is that the birds are calling as they're flying, so you get to "hear" the migration as well as see it.
In lesser numbers to the Yellow-faceds are White-naped and Scarlet Honeyeaters, Eastern Spinebills, Noisy Friarbirds and Red Wattlebirds, along with both Spotted and Striated Pardalotes. Many Silvereyes also pass over, though the vast majority of them actually migrate at night.
Although the migration isn't overly well-known among people the word is well and truly out amongst the local raptor population and one will almost certainly see things like Australian Hobbies, Peregrine Falcons, Brown/Grey Goshawks and Collared Sparrowhawks patrolling the area. The migration often "pauses" when a raptor is cruising around and once gone, the spectacle starts again.
You need to time it right though. The best days are those beautiful crisp, clear and still autumn mornings, often following a crystal clear night. If it's windy, cloudy or rainy you're not likely to see many birds. The best times appear to be between about 9am and 11am but sometimes on mornings that remain clear and still, the migration can go past midday.
And although the major bottleneck appears to be around Pambalong, the migration of honeyeaters is certainly not restricted to the western edge of the Hunter Estuary. The passage of Yellow-faced Honeyeaters and Noisy Friarbirds in particular can be seen from other parts of the Hunter Valley, from Maitland up through the Upper Hunter to Murrurundi; mostly where there are some vegetated corridors for the birds to follow. So keep your eyes (and ears) peeled this autumn to see if you can catch some of the great Honeyeater Migration!