Post-Zambia, I had a great 3 days in Suffolk during a brilliant time of year to visit for spring passage, with waders moving through and the first summer migrants arriving on territory.
 
Highlights included plenty of Skylark in full song, a fair number of passage Wheatear, and Dartford Warbler at Dunwich Heath. A real highlight was the Zitting Cisticola at Walberswick, while Minsmere was particularly lively with abundant Sand Martin, a singing Nightingale, hundreds of Sandwich Tern, and a Spotted Redshank.
 
Over the three days I was very happy to amass 101 species, with the full trip report found here.

This Easter I spent a week travelling in Zambia with a group of friends, which was an amazing opportunity to see some entirely new wildlife compared to that which I have seen in the past. Having never travelled to Africa or south of the equator before, the diversity of new bird species was pretty overwhelming.
 
The journey began with a connecting flight via Jomo Kenyatta International Airport in Nairobi, Kenya. Despite feeling very groggy at 5.30am after the 9-hour stint, I was so eager by the prospect of the many new species that this trip would provide that I wanted to see if there were any lifers visible from the airport windows. It was here I saw my first Pied Crow and African Pied Wagtail (two species that I would see many more of across the trip), as well as a smattering of African Palm Swifts.
 
Upon our arrival in Lusaka on Friday morning, we were all very tired and birding wasn’t the top priority. We spent a large chunk of the day driving south to Kiambi Lodge where we would be spending the next few days. While the extreme tiredness was setting in on this journey, the drive wasn’t devoid of birdlife. In fact, 5 hours into our long journey we were treated to a Spotted Eagle Owl toying with a snake directly on the road in front of us, lit up by the headlights.

​Our three nights at Kiambi Lodge were absolute paradise for someone interested in wildlife, with birds seemingly everywhere you looked or listened. That said, as a first-time visitor to Africa, this abundance of species came with challenges. Almost everything was unfamiliar: songs, calls, silhouettes, behaviours etc. As such, confidently identifying species proved difficult and at times frustrating (especially when a bird only offered a fleeting glimpse before disappearing).
 
This was most apparent on my first morning walk alone, when I was suddenly surrounded by entirely new sounds and movements. However, over the following days patterns began to emerge, which was helped enormously by local guides, online and physical resources, and my friend who spends a lot of time working in Zambia. The more common local species gradually became more familiar. Following that first walk, and after spending some time with a field guide, I could say with confidence that I had a Village Indigobird, a Variable Sunbird, numerous singing Laughing Doves, and a Marsh Warbler in full song (the song was similar to the Reed and Sedge Warblers I know from the UK, but more complex and musical), though it’s hard not to wonder how many other species were present that I failed to identify!
 
Later in the morning, we visited a local banana farm, where I saw a number of new species among which included Common Waxbill, Bronze Mannikin, Southern Cordonbleu (a favourite of mine), Common Bulbul, Familiar Chat and Red-billed Quelea (which unknown to me at the time became the most common species across the trip).

​The day continued with a fantastic boat ride on the Lower Zambezi River, where we were treated to our first good views of the African Fish Eagle, Zambia’s national bird. One thing that struck me was its call, sounding halfway between the cry of a ‘typical‘ bird of prey and a coastal gull (which makes sense, given it’s a fish-eating eagle, an eagle that’s spent a bit too long hanging around with gulls?!). On the boat ride, we also had our first encounters with a colony of White-fronted Bee-eater, as well as Little Bee-eater and a single European Bee-eater (one of the few species across the entire trip that I’ve seen in the UK before). The kingfisher diversity was also striking, with numerous Pied Kingfisher and a single Brown-hooded Kingfisher (though I would see a number of other kingfisher species across the trip). On the banks of the river we also saw various Blacksmith Lapwing, White-crowned Lapwing, Water Thick-knee, Hadada Ibis, and singles of Goliath Heron and Hamerkop. As well as the avian diversity, we were treated to likely over 50 hippos which were gathered in large bloats (apparently the collective noun for hippos…) that were impressive but slightly intimidating, particularly when the guide cut the engine and we were left drifting silently among them.

​On Easter Sunday 5th April, I perhaps had the most enjoyable day of the trip during a full-day game drive in the Lower Zambezi National Park. We were treated to practically every mammal species that you are likely to see in the park (including Elephants, Wild Dogs, Warthogs, Chacma Baboons, Kudu, Buffalos, Waterbucks, Impala, Zebras and even an elusive Leopard), and the bird life was fantastic. The day brought with it 74 bird species – too many to list here but there were a few highlights.

Very early during the drive we had excellent views of an immature Martial Eagle, a hugely powerful bird of prey which perched perfectly in the morning sun for us to observe it for a few minutes before bounding away. A little further into the park we were lucky to see 3 Southern Ground-hornbill which were feeding away on the small prey in the grass, as well as a small flock of Helmeted Guineafowl, 2 White-faced Whistling Duck and a Grey Go-away-bird (possibly my favourite species name of the trip). We also had great views of a Red-backed Shrike (a species I’ve now seen in Zambia, Corfu and Scilly).

​As previously mentioned, the kingfisher diversity on the game drive was amazing, adding Woodland Kingfisher and Grey-headed Kingfisher to the trip list. A real highlight of the game drive was also stumbling upon a flock of vultures feeding on what may have been the leftovers of a successful wild dog hunt. In just one confined area, there were 4 species of vulture, 3 of which are critically endangered: White-headed vulture, Lappet-faced Vulture, Hooded Vulture and White-backed Vulture.

​In the same area, we had our first Eastern Paradise Whydah flying overhead, a bizarre bird whose males grow extraordinarily long tail streamers. These tails are a classic product of sexual selection: females preferentially choose males with longer, more elaborate tails, not because the tail itself is advantageous, but because it acts as an honest signal of underlying genetic quality (with beneficial genes linked to or indicated by those controlling tail length), driving their evolution even though they impose clear costs to flight and increase predation risk. It’s a striking example of how sexual selection can favour traits that would be selected against under natural selection alone. This was particularly obvious when watching them in their clearly awkward and laboured flight. Their flight looked so inefficient it prompted a friend to point out that it looked like the bird from Flappy Bird. Outside the breeding season, males shed these elongated feathers, making flight far more efficient again.

A lunch stop near on the banks of the Lower Zambezi presented some familiar wader species which can be seen in Europe, including Common Sandpiper, Greenshank and Ruff, as well as the very unfamiliar sight of Saddle-billed Stork. Just before, we also had very nice views of a Squacco Heron, one of my absolute favourite species of the trip (though I’m not sure why…). Lunch was cut a little short however by the appearance of a buffalo, which prompted us all to rapidly get back in the Jeep due to their propensity to charge.

​Towards the end of the drive, we spotted a beautiful male Kudu. While in itself this is a highly impressive and imposing antelope species, I was mainly drawn by the fact that it clearly had a Red-billed Oxpecker feeding on its back. This is an ecological interaction that comes up when teaching school biology. Oxpeckers are a particularly useful example when discussing feeding relationships because they don’t fit neatly into a single trophic level. While they remove ticks from grazing animals and act as “cleaners”, they also feed on blood and other host-derived resources, meaning the relationship can shift between mutualism and parasitism. This makes them a nice, real-world case study for the complexity of food webs.

A final highlight of this day was seeing the many Cattle Egret. This is a species I am familiar with, seeing various flocks locally to Oxford, as well as a flock that frequent The Boathouse in Cornwall where I have spent a few days in the last two Autumns. However, my experience with them on this drive was very different given the fact that they were flocked close to a pair of mating Elephants!

​Monday 6th April was our final day at Kiambi. We took another morning boat trip which supplied a few more new species for the trip list (as well as lifers for me). This included an African Darter and the aptly named Cut-throat. A highlight were some nice views of a Malachite Kingfisher, which was both the smallest and most delicate kingfisher species seen so far, as well as being most similar to the species I am used to seeing in the UK, as well as a Little Heron​.

​We left Kiambi and proceeded on the long drive to Lake Kariba, where we had a fantastic 2 nights aboard a houseboat. The lake itself is man-made, created in the late 1950s when the Zambezi River was dammed to form the Kariba Dam, at the time one of the largest engineering projects in the world. Today, the dam remains a crucial source of hydroelectric power, supplying around a third of Zambia’s electricity.

The change in habitat brought a change in species, with my first sightings of White-winged Black Tern and Grey-hooded Gull. The latter of these is the only regular gull species in Zambia, which is funny as I consider gulls to be one of the more numerous taxa of bird in the UK , and it wasn’t long ago that I was in Niagara Falls, often cited as one of the best inland locations for gull diversity, where double-digit species can be seen in a single visit. Lake Kariba was also the place to be for African Fish Eagle, where I counted 12 individuals along our ride from Siavonga to Lotri Bay.

​We docked on a very small island near Lotri Bay and spent the evening and following morning around this area. Though of course very different to the UK, it struck me as functioning in a surprisingly similar way to islands like the Isles of Scilly, where I’ve spent a lot of time birding. Small patches of land acting as natural stopover points, concentrating a high diversity of birds as they cross large expanses of water and pause to refuel. Species highlights from this area included Tawny-flanked Prinia, Lilac-breasted Roller, Trumpeter Hornbill, Reed Cormorant, Black-collared Barbet, Rattling Cisticola, White-bellied Sunbird, Southern Red Bishop, Red-winged Starling, Brown-necked Parrot (which took a while to pin down even though the calls were heard a number of times) and a wonderful Red-chested Cuckoo.

Wednesday 8th April was my birthday, which started with a drive back from Siavonga at Lake Kariba towards Lusaka (during which we had brief views of a Black-winged Kite). We had lunch at the Lilayi Lodge, a private reserve where we were treated to a Swainson’s Spurfowl, African Golden Oriole and a flock of White-crested Helmetshrike.

I left Zambia on 9th April, with one final addition to the trip list coming somewhat unexpectedly, a Cape Wagtail seen on the airfield during my layover in Johannesburg Airport (an understated end to a week that had been anything but!). The trip was without doubt the most intense period of birding I’ve experienced in terms of the number of new species encountered in such a short space of time. In total, I recorded 137 species, 116 of which were lifers. Full eBird trip report can be found here.

I have recently started a full time teaching job in London, which alongside its many pleasures includes the fact that there is a 2 week October half-term which nicely coincides with a great time to visit Scilly for birding.
 
The trip started on a slightly disappointing note when the Scillonian’s crossing was cancelled due to rough sea conditions. However, I was very lucky to be down in Cornwall anyway with my parents so managed a day of birding on the mainland. I had an unsuccessful twitch of the Steppe Grey Shrike (seen by one observer the day before) near Mullion, but did add 3 species to my Cornish list: a Reed bunting at Gunwalloe, a few Great Crested Grebe on The Loe, and a Tawny Owl at Mawgan Creek. These all showcase my bias towards visiting Scilly, given that they are all fairly common birds on the mainland but reasonably rare on the islands. Additionally, it was my second time staying at The Boathouse in Mawgan, a beautiful spot nestled in woodland but also on an extreme tidal area of the Helford. Despite only spending 6 nights there total, my life list for The Boathouse is only ten below the home I grew up in in Buckinghamshire and have lived in for years (56 vs 66)!

​When it came to the delayed Scillonian sailing on Tuesday 21st October, the crossing was fairly quiet on the Scilly-side of Wolf Rock, save for one Arctic Skua (a Scilly tick for me) and good numbers of approximately 70 Guillemot. Upon arriving on St Marys, I caught up with the many Black Redstart that are on the islands this time of year, with eight on Porth Mellon (on one of the days, it seemed likely that there were 25+ across St Marys alone). On a walk around the island, news broke that there was a Red-backed Shrike on Porthloo Lane, which I twitched with a number of other birders. Amazingly, it has just hunted a Scilly shrew which was skewered next to it. Following this, I walked to Telegraph where there was one Yellow-browed warbler calling as well as a Little Bunting in one of the nearby clover fields. Although it was actually seen best when flushed to the tracks leading to the cottages.

​On Wednesday 22nd October, I got up just before sunrise in hope to see the MEGA Eyebrowed Thrush that was seen when I was sailing the previous day (but not since I arrived on the islands). In low light, I arrived in the Porthloo Duck Pond area and began scanning the various areas of leaf litter. Andrew Allen, one other birder on the islands, was also on the lookout, when he spotted it feeding at the base of some trees. Together, we had 5–10 minutes of watching it before we lost sight. I bird flew from the trees above and headed NE calling like a redwing, so I assumed this was the EB thrush. Although the viewing time was limited (and I didn’t get any photos), it was still a thrill to see it! After breakfast, I headed to the harbour to catch a boat to Tresco for the day, before which I found a Common Scoter in the bay from Tregarthens. Upon arriving at Carn Near, Tresco, the area south of the heliport was rife with Stonechat, and I had my first Scilly Fieldfare (although there were many more to come across the trip!). I walked to the south beaches of Tresco, one of my favourite spots on all the islands that always has good numbers of shorebirds. Sanderling numbers were fairly low, with just 13, along with 30 Turnstone, 30 Oystercatcher, 18 Common Ringed Plover, 4 Whimbrel and 2 Bar-tailed godwit. It was striking just how few Wheatear there were on the trip as a whole – the 3 I had along this walk were among only 4 in total.

​I then had a good tramp around the Abbey and Great Pools, adding Redpoll to my Scilly list as 3 flew over (along with 16 Siskin). Duck numbers were good on Great Pool, with 2 Shoveler, 68 Gadwall (my highest count on Scilly), 5 Wigeon, 28 Mallard, 14 Teal and 1 Pochard. After lunch, I walked along Back Lane where I had my first Golden Plover of the trip.

​Thursday 23rd October was challenging conditions for birding, with high winds and many showers. I decided to stick on St Marys, which turned out to be a good decision as I added 3 species to my Scilly list. In the morning, a Jack Snipe was flushed along the path through Lower Moors, as well as seeing one Lesser Whitethroat. I decided to walk around Peninnis via the farm trail and Old Town Bay (where the Great White Egret that had been making its way around the islands was fishing). I bumped into Will Wagstaff, who had just found a Water Pipit near Peninnis, which I twitched briefly as it foraged in a mixed pipit and finch flock. On Peninnis itself, I came across an unusual snipe. It was roosting relatively openly and in drier patches and didn’t flush as easily as other Common Snipe. Additionally, it had a less zigzagging flight pattern, and didn’t call when flushed. However, no diagnostic features for any vagrant species were ascertained.

​News of an Ortolan Bunting on Porth Hellick meant I crossed the island (via Higher Moors where the Great White Egret had now relocated). I spent roughly half an hour scanning the mixed finch flock on the beach with no avail, though I did get nice views of two Brambling. As the light began to fade, I walked back to my BnB via Holy Vale, where a Woodcock was roosting.

My day on Bryher on the 24th October was reasonably quiet. There were good numbers of Chiffchaff on the Eastern side, presumably blown through the island via the strong westerlies, but no hoped for American vagrants. Also, one Ring Ouzel on Stinking Porth, but the highlight of the day was ironically on the boat trip back to St Marys, when a Peregrine showed very well flying over Tresco Channel.
 
The story was similar again on St Martins on 25th October, with good numbers of Chiffchaff, but nothing else too exciting. Chapel Down did bring me my first Raven of the trip, as well as 7 Skylark.

​On Sunday 26th, my final full day, the clocks changed allowing for an earlier start. I walked a decent distance around St Marys in the morning, briefly seeing (but clearly hearing) the Lapland Bunting which was in the Porth Hellick area. After my morning tramp, I decided to catch a boat to St Agnes, but not before trying to see the 2 Spoonbill that have taken up residency off Samson. These two individuals were here last year as well, but I have consistently failed to add them to my Scilly list due to bad weather conditions and never getting a boat close enough to the islands. However, the light was good and visibility clear on Sunday morning, so I got out my scope at The Garrison and managed to view one individual distantly. It’s lucky that they are such a distinctive species!
 
I had a great day on St Agnes, twitching the American Buff-bellied Pipit with a number of other birders, as well as being extremely lucky with a flyover of 2 White-fronted Geese (a very difficult bird to catch up with on Scilly). There were very good numbers of Common Ringed Plover on Periglis, with 19 in total along with 2 Curlew and various other shorebirds.

​Despite the earlier sunset, I quickly made my way to Porth Hellick when landing back at St Marys to twitch the Bluethroat, which I just about got some good views of before the light completely went (another Scilly tick!).

On my final morning, I spent a decent amount of time trying to pin down the Hoopoe that had been spotted in various sites around the Garrison. Eventually, I viewed it well feeding at the campsite – I was glad to catch up with it before boarding the Scillonian. The sailing back to Penzance was much more productive than the outward journey, with 1 Great Skua, 3 Puffin, 18 Guillemot, 180 Kittiwake, 1 Fulmar, 11 Great Shearwater, 2 Sooty Shearwater and 7 Manx Shearwater (all west of Wolf Rock). There was also a great moment where a Merlin bombed towards the ship, briefly landing on one of the masts before continuing onwards towards Scilly!

The trip was very much a success. I had 6 lifers, added 8 species to my British list, 16 species to my Scilly list, and 17 to my 2025 World list. Full eBird trip report (for Scilly specifically) can be found here.

I have just returned from another cracking week in Scilly. Last year was my first time visiting during the spring, and despite spending every summer in Scilly, I was surprised at how unfamiliar much of the islands’ flora and fauna was in April. Landscapes are transformed as the relatively dull heathy areas in the summer pop out with waves of bright yellow gorse flowers, while the spring soundscapes around reeds and hedgerows are elevated with the song of migrating warblers. While I was expecting this seasonal change a little more this time round, the trip still brought some great surprises.
 
The week started with challenging birding conditions with heavy rain on the Scillonian, making it difficult to pick much out on the sea other than some Manx Shearwater, with approximately 160 along the entire journey (they always seem much more numerous closer to Land’s End than the Scilly-side). The wind and rain persisted over the first couple of days on Bryher, which in combination with me missing Scilly’s Hoopoe-influx during the week prior to my trip was a bit of a downer. However, while the birding was difficult, it was not impossible, with a Great White Egret at Popplestones and Great Northern Diver at Great Porth. Also, the first signs of Wheatear and Ring Ouzel. In the case of these latter two species, my experience was very different compared to April 2024. This year, Wheatears were very thin on the ground, with only 15 over the entire trip, whereas last year there were as many as 20 on single short walks. In contrast, last year I only had a single male Ring Ouzel, but this year I saw at least 6 individuals (that’s twice as many Rouzels as Blue Tits!).

With the arrival of the rest of my family, we moved islands to Tresco. I was excited about this as this island has two large pools which have historically drawn in some interesting birds. However, the water levels were very high this year, with a distinct lack of muddy fringes to tempt down any waders. Instead, I spent most mornings on Tresco’s south beaches. This is one of my absolute favourite places in the world, as the rising tide pushes the shorebirds inland under the morning sun. Numbers were fairly good this year, with one morning producing 22 Oystercatcher, 18 Common Ringed Plover, 19 Ruddy Turnstone and 72 Sanderling. A real highlight was discovering that one of these Sanderlings was colour-ringed. Upon requesting the details, I found out that it was 5-years-old, first ringed in Pontevedra, Spain in October 2020 and seen once since in Syddanmark, Denmark in July 2022 (a distance of approximately 2000km!).

Over the next few days on Tresco, the trip list began to level out, although during a 45 minute sea-watch I had my first Scilly Black-throated Diver off St Helens. The birding all seemed to calm down a little, but that changed when on my final full day there was a report of a Shore Lark on St Mary’s. This is a very scarce bird on Scilly, with this individual being only the 13th ever and the first since 2009. I hoped that it would stick around until the following day, and that I would have time to catch up with it before my Scillonian departure. I hitched a lift on one of the airport taxis and walked to Porthellick Down, where it was most recently seen. After a challenging 30 minutes with a suspected view as it flitted past and down to the rocky shore, it finally showed well on the coastal path. A really smart male of North European race, it continued feeding, associating with a Wheatear before being flushed by a dog walker. Speaking to other birders, I’m always aware of comparatively just how small my Scilly list is (144 species, with many others around the 250-300 mark). However, it's these trips in Autumn and Spring that will slowly bring my list up as unusual finds such as the Shore Lark drop down to the islands. All the more reason to visit outside of the summer season!

I ended the trip with 83 species (3 less than last April), but with 5 species added to my Scilly life list and 21 to my UK Year List. Full ebird trip report can be found here.

At the start of last year, I shared a blog post of my birding highlights from 2023, a year that stood out as my best yet. I recorded 21 more species than the year before, including 36 species I had never seen previously. I noted that this was likely due to two main factors: dedicating more time to exploring local patches and taking a few trips to new destinations. Looking back on 2024, it’s clear that the latter underscores just how much global bird diversity there is to offer.
 
Across 2024, I saw 359 species, almost doubling the number I saw the previous year and adding a whopping 161 lifers. Over the past few years, I haven’t travelled internationally all that much, but in 2024 I had the opportunity to visit Italy, Switzerland, France, Greece, Canada and the US (as well as visiting Scilly in the spring and autumn alongside my usual summer trip). These trips, particularly to north-east America, were the driving force behind my bird numbers. The dramatic increase in my bird life list highlights the importance of evolutionary history and species divergence in shaping global avian diversity. Travelling across the Atlantic to North America, for example, introduced me to species that have evolved independently from those in Europe due to millions of years of geographic separation. Each region has its unique assemblage of birds, shaped by distinct habitats, climates and evolutionary paths, which makes exploring new areas such a rewarding experience for birders.
 
It was hard to whittle down all my birding experience from this year into a Top 10, but I have done my best based on the initial excitement I had in the moment. It’s striking just how much travel has influenced this list – while last year’s highlights were all from the UK, this year half of my Top 10 occurred abroad.
 
Top 10 2024 bird moments:

1. A black kite drifted across Tresco on 24th April during an early morning visit to some dried up floods, mobbed by gulls, and shortly followed by a red kite and a female marsh harrier - all within 30 minutes. A remarkable trio of raptors I’d never seen on Scilly before.
2. I briefly caught glimpse of an unknown bird which seemed a mix of thrush, nuthatch and wagtail on 23rd September at Presque Isle State Park, Erie, Pennsylvania. On consulting my National Geographic bird guide, I identified it as a northern waterthrush - one of my favourite lifers during my travels in north-east America.
3. On a walk along Buzza Hill, St Mary’s, Isles of Scilly, on the 27th October I caught sight of a bird I’m only used to seeing in the spring – a lesser whitethroat. I managed some photos and pinned down a few characteristics that classed it as an eastern-form of the species, circulating the news on the Scilly Birding WhatsApp group. It’s easy to get swept away with the many other birders finding rare birds at this time of year on the islands, but this was self-found and really made me feel I was contributing to the birding community.
4. In a Gerald Durrell-esque afternoon on the 23rd August, I watched from the balcony of a holiday apartment as a few eastern olivaceous warblers hopped between the trees in an olive grove in Paxos near Corfu.
5. On 23rd April, a male ring ouzel on the north end of Tresco caught my attention with its ‘chacking’ call, before suddenly appearing at the foot of the ruined King Charles Castle.
6. Watching the black skimmers tracing the water’s surface at sunrise on Cape May Beach on 9th October was a real highlight of my North American trip. Despite their size and unusual bills, they were very elegant in their tight flock, and contrasted the hundreds of royal terns streaming through the beach in the opposite direction.
7. During my first birding walk of the North American trip, I heard a loud rattle from one of the ponds on the Toronto Islands on 16th September. It was a belted kingfisher, even brighter in colour and much larger in size compared to the kingfishers I’m used to in the UK, and was the start of the many more 'tropical' birds I would see over the next month.
8. Twitching a pair of serins on 24th October was a truly Scillonian birding experience. Among tens of other birdwatchers with their binoculars, scopes and huge camera lenses, we waited for over an hour, scanning the various finches that flitted up and down in an unceremonious pumpkin field behind a fire station. Finally, we were able to pick out a flash of yellow and the serins posed on a dead sunflower for a little while for us all to admire.
9. Finding a little owl snoozing unnoticed in Peckham Rye on 21st June was slightly surreal, as people passed by on their lunch break, oblivious to the bird.
10. During my first ever time skiing, it was obvious that the mountains around Cervinia were pretty desolate of bird life, apart from the ever squeaking alpine choughs. But during lunch on 22nd January, a flock of white-winged snowfinches flitted down to a table, much as sparrows do at picnic benches in the UK. It was quite odd seeing a sign of birdlife amid the miles and miles of unbroken mountains and snow.

I was recently reminded in conversation of a topic in biology that I find fascinating, not only due to the sometimes described ‘paradoxical’ evolutionary nature of its existence, but also due to the potential biases that have surrounded its study for centuries.
 
Across the vast diversity of the animal kingdom, one behaviour has often baffled biologists: same-sex sexual behaviour. This is not the same as a homosexual orientation in humans, which more closely aligns with what is referred to as same-sex sexual preference (i.e. when individuals are more likely to undergo sexual behaviour with individuals of the same sex as themselves when different-sex partners are available). From penguins to primates, and even insects, same-sex sexual behaviour is common across species (for a great book on this, see Joan Roughgarden’s “Evolution’s Rainbow”, or Bailey and Zuk’s shorter review paper). But why would animals invest in behaviours that don't directly lead to reproduction? Isn’t that an evolutionary dead-end? This question has sparked many studies, arguments and controversy among the research community, with scientists traditionally framing same-sex sexual behaviour as an evolutionary costly behaviour that begs for an adaptive explanation. An alternative perspective, however, turns this idea on its head: the "ancestral indiscriminate sexual behaviour" hypothesis.
 
This challenges the notion that animals evolved from ancestors engaging exclusively in different-sex sexual behaviour, from which same-sex sexual behaviour has evolved. Instead, it suggests that the earliest sexual behaviours weren’t sex-specific at all, but animals directed their mating efforts at whoever was available, regardless of sex. Could this ancestral state explain the persistence of same-sex sexual behaviour in the animal kingdom today?
 
To understand this, we must imagine the world’s first sexually-reproducing animals. These were different to the complex multicellular animals that we are used to seeing on our TV screens today, with nature documentaries often showcasing male animals jostling it out to impress the females and attain mating opportunities. Long before elaborate courtship rituals emerged, these ancestral species didn’t have the ability to finely-tune mate recognition. Instead, we must picture a much simpler organism, consisting of just one cell. Billions of years ago, these single cells began to swap, shuffle and merge their DNA with one another, creating new cells with unique genetic combinations. While it may not resemble the intricate processes we see today, this was the humble beginning of sexual reproduction and behaviour.
 
Sexual reproduction gave organisms an edge over asexual ones by mixing genetic material, allowing offspring to adapt better to changing environments compared to clones produced through asexual reproduction. As is often the case in evolution, this new method of reproduction sparked competition between individuals, where some cells wanted to become smaller and more mobile to increase their chances of fertilising others. Because these smaller cells contributed fewer resources to new offspring, it became necessary for other cells to evolve to become larger and more nutrient-rich, so that new and developing offspring had enough energy to survive. It was this evolutionary race for reproduction that ultimately led to the evolution of biological sex, where two distinct sex cells (called gametes) evolved: male sperm and female eggs.
 
The crux of the ancestral indiscriminate sexual behaviour hypothesis lies in this evolutionary timeline of events that led to sexual reproduction and biological sex. For sperm and eggs to evolve, sexual reproduction must have come first. As a result, the earliest sexual behaviours were likely ‘indiscriminate’, aimed at increasing mating opportunities by attempting to reproduce with all individuals rather than selecting partners based on their biological sex, which was in the early stages of evolving. The result? A natural mix of same-sex and different-sex interactions.
 
For those early species, life was all about maximising reproductive success in challenging environments. Picture a group of primitive animals releasing eggs and sperm into the ocean. The goal was simple: fertilise as many cells as possible. In such scenarios, being overly selective about your mate’s sex could backfire. By directing sexual behaviour indiscriminately, individuals increased their odds of successful reproduction. In this ancestral world, missed opportunities could be far more costly than the occasional same-sex interaction. Evolution, after all, isn’t all about perfection, it’s about what works well enough to pass on genes.
 
The hypothesis therefore suggests that same-sex sexual behaviour isn’t some evolutionary oddity that evolved later, but instead it was simply part of the package. In fact, targeting sexual behaviour exclusively toward the opposite sex may be the derived, more specialised trait that evolved in specific contexts. In other words, same-sex sexual behaviour hasn’t evolved repeatedly in specific animal groups as many scientists have previously argued, but instead persists as a relic of the earliest sexual behaviours.
 
This perspective allows us to recognise some of the biases that have historically stung scientific research. Much of the 19th- and 20th-century work on same-sex sexual behaviour was likely prejudiced by heteronormative assumptions and Euro-American cultural norms, where discrimination against queer individuals may have contributed to framing same-sex behaviour as unnatural or in need of special justification. By shifting our baseline to consider indiscriminate sexual behaviour as the ancestral state, we can move beyond these biases and gain a clearer understanding of the rich diversity in animal behaviour. It reminds us that same-sex sexual behaviour is part of a broader, ancient behavioural repertoire, not some unusual exception.
 
It's important to approach this shift with caution, as science can sometimes be coopted to support subjective and dated beliefs about what is ‘natural’ in humans. It seems in modern times we are frequently seeing science being misused to justify discriminatory positions on gender, sexuality, and behaviour, such as rigid gender ideologies or assumptions about what human identities should or shouldn’t be. This risks oversimplifying complex biological and social phenomena and inappropriately applying conclusions from the animal kingdom to human society.
 
However, the ancestral indiscriminate sexual behaviour hypothesis provides a fresh lens through which to view same-sex sexual behaviour. It suggests that this behaviour isn’t an evolutionary paradox or a costly mistake, it’s a window into the ancient roots of animal behaviour. By recognising same-sex sexual behaviour as a natural and persistent trait, we can better appreciate the diversity of life and evolution’s complex, intricate and messy beauty.

All in all, I ended my trip with 96 bird species seen, including 24 new personal species for Scilly and 4 new species globally (full eBird trip report found here)! I cannot recommend Scilly in the autumn enough for anyone who enjoys birdwatching, and I am already keen to book my trip for next year!

As a post-PhD break, I have just spent a month travelling over land around Canada and the north-east USA. It was an incredible trip, where I got to see a wide-range of cultures in different cities and towns, as well as some top quality birds. Due to the nature of the trip, I was unable to take my camera for wildlife photography, but it was still great to get out into natural spaces and explore the local wildlife!

The real highlight for me was my final week at Cape May, in the southern tip of New Jersey. Cape May is famed for its birding, particularly during the spring and autumn when huge numbers of migratory species are seen. The narrow peninsula acts a bit like a funnel to the migrating songbirds, hawks and waders, channeling them towards the very tip of the peninsula where they briefly rest before making long journeys over sea or land. This effect is very noticeable when birding at specific spots, such as the Cape May Bird Observatory's Hawkwatch platform, where one morning we had 8 bird of prey species including 35 ospreys and approximately 50 turkey vultures. Having never birded this side of the Atlantic before, I decided to book onto a tour group so that I could have a little help with identifying unfamiliar species. This was much needed as I ended my time in North America with 125 species I had never seen before! My entire eBird trip report can be found here.

I'm really pleased to say that I passed my PhD Viva today without corrections, which means I am now officially a Doctor of Biology! The viva involved an interview process with two professors in similar fields of biology asking lots of questions as to the reasoning behind my research as well as my key findings. Despite being a nerve-wracking process, it was also a great opportunity to talk to experts in the field as to how my research fits into the wider context of evolutionary and ecological research. It goes without saying that I couldn't have achieved this without the professional and personal support of my supervisors (Ben, Josh and Ella) and the rest of the research group at Oxford - thank you everyone and on to the next chapter!

Spotted flycatchers are very much a 'Brill bird' to me. Brill, a small village on the Buckinghamshire side of the Bucks/Oxon border, is where my parents live and where I grew up. The unusual thing about the village is that it is on top of a hill at roughly 120m altitude in an area of generally very flat land. To me, this seems a likely reason as to why it draws in a few migrating species during the autumn that hit higher land on their long flights. Spotted flycatchers are a migratory species which breed across the UK and overwinter in tropical Africa. The UK breeding population has taken a real hit over the last few years, dropping by 92% between 1967–2020, making them a red list species that aren't particularly easy to find. The reason for this severe decline is somewhat unclear, but is likely linked to climate change at their wintering sites as well as a loss of insects and suitable habitat in the UK. Despite this serious decline, I came across no less than four on a walk through the village common today, which was a real treat!