Sun, sea, sand and smell. Maybe that’s not the way they’d say it in the tourist brochures, but it’s the perfect description of Michaelmas Cay.

No other wildlife spectacle is quite such an assault on the senses as a seabird colony. With up to 20,000 noisy, active, and pretty smelly birds on a small, sandy island, a visit to Michaelmas Cay is a must for any serious birder touring north Queensland.

I leave on the first boat to land on the cay each morning to get uninterrupted views of the birds before the other tourist boats land there. Skipper Carl tells me the sea has been choppy for the past week or so, but this is a perfect morning: fine, clear and calm, as we set out from Cairns on the 90-minute crossing.

Once there, First mate Vinny, an amiable Brazilian, gets me straight into the inflatable rib and deposits me on the beach, where I stand and stare in sheer awe at the birds around me. I’ve been to many seabird colonies before, and seen puffins on Shetland and penguins in Antarctica, but in 50 years of birding this is my first visit to a tropical one – and I’m not quite prepared for just how overwhelming the experience proves to be.

What to do first? Scan with my binoculars or start to take photos? I do both, alternating between the two like a child who can’t decide which Christmas present to play with, as I metaphorically unwrap delight after delight.

Should I look at that family of brown boobies – closely related to the gannet – the male and female carefully shading their panting chick from the harsh sunshine? Then there are the flocks of brown noddies – a tropical tern with a chocolate brown plumage and pale cap – gathering just a couple of metres from me on the sandy beach, the water lapping at their feet. Also the graceful sooty terns, which are among the most elegant of all flying birds, able to spend years in the air without coming to land.

I try to recall the advice my wife, Suzanne, gave me before I came out here: live in the moment, and just stop for a moment to take in the wonder of what you are seeing (and hearing and smelling!). So I methodically scan through the birds, picking up the scarce black noddy and the comical-looking red-footed booby, before focusing on the spectacle as a whole.

Seabird colonies are all about quantity. There are just a dozen species here: but the lack of variety doesn’t matter when there is so much to take in. I gaze upwards into the clear, blue sky and watch great and lesser frigatebirds – the pirates of the seabird world – floating effortlessly in the ether like giant black kites.

Unlike the other seabirds here, frigatebirds are unable to land on the surface of the sea because their plumage is not waterproof. This forces them to be kleptoparasites – chasing down smaller birds and forcing them to regurgitate their meal – so the terns are understandably wary and give them a wide berth.

I take hundreds of photos, often having to zoom out to the wide end of my lens to accommodate the sheer number of birds around me. An hour later (though it feels as if I have been here only a few minutes), Vinny comes to collect me and take me for a tour of the back of the cay.

This is my chance to pick up some of the species that have so far eluded me: crested and lesser crested terns (the former with a lemon-yellow bill and the latter with a deeper, orange-yellow one) and, best of all, a small group of black-naped terns, a much smaller species found in the Pacific and Indian oceans that I’ve never seen before. They are very attractive compared with their larger and bulkier relatives, with a luminous white plumage and delicate black markings from the eye to the back of the neck.

We also see a couple of turtles, and an adult manta ray being followed by a young one; a timely reminder that I need to look beneath the surface of the water as well as above it.

Then it’s back to the boat, a welcome lunch (birding always makes me hungry!) and an afternoon spent swimming over the nearby Hastings Reef. I search for (and eventually find) the clownfish – the eponymous Nemo from one of my favourite children’s films – and don’t make such a fool of myself when snorkelling as I usually do.

On the journey back, it’s hard to recall the highlights of my visit because there are so many. But as I scroll through dozens of photos on my laptop that evening, I feel privileged to have enjoyed such an overwhelming sensory experience, thanks to the thousands of seabirds on Michaelmas Cay.