Pallid Swifts & Spotted Crakes

Last week was an exceptional week and migrants continued to arrive every day. I added several species to my year list and even had a few lifers, with Spotted Crake being the undisputed highlight.

Spotted Crake, La Bassa dels Pollancres, Delta Llobregat

A patch tick came in the unexpected form of a Rock Sparrow, after being given a tip-off to a single spot within the delta boundary that holds a few birds. I undertook the 30 minute cycle and almost immediately connected with 4 birds, sitting on top of wires, a habit seemingly not too uncommon in the species, seeing as this is the manner in which I ticked them, last year at Garraf.

Rock Sparrow, Delta Llobregat

Black-winged Stilts came back in numbers, and I also had my first Little Bittern (adult male - Cal Tet). Garganey continued to pass through in decent sized flocks, with a personal maximum count of 19. An Osprey showed well around Cal Tet throughout the week, at one point bathing in the river at Nelson Mandela bridge, where it was chased off by a pair of Hooded Crows - a Catalan rarity which bred locally for the first time last year. There have also been a constant trickle of Ruff, Spotted Redshank, Green Sandpiper and Little-ringed Plover. 

Migrant Garganey, Cal Tet, Delta Llobregat

Black-winged Stilt, Cal Tet, Delta Llobregat

Osprey being seen off the one of the local Hooded Crows, Nelson Mandela Bridge

Much to my delight I picked up a flock of swifts over Cal Tet lagoon, and with the early date I immediately suspected Pallids. They were a lifer for me and thus I had no real experience. They bombed about so fast I found it hard to pick up any of the features I had read about - whiter throat, blunter wing-tips, scaly underparts, browner colouration (all in comparison to Common Swifts). I took a few pictures, and luckily all of these features were visible back home - they were definitely Pallid Swifts. The following day there were still good numbers and I saw these features better, and also heard the call - which is really different. 

Pallid Swift, Cal Tet, Delta Llobregat

On Saturday I decided to cycle to Remolar Filipines to look for migrants. I'm always slightly put-off by the sheer number of people there, because I find it quite difficult to relax and concentrate on the birds. The first hide was really quite busy. I saw two Wood Sandpipers, which were a year tick. Happy with this, I left to try to find a quieter spot. I decided to head to the other hide, which is usually quieter. I checked any open muddy areas, dreaming about small crakes and Bluethroats on my way, all to no avail. 

When I reached the next hide I sat and scanned. I saw a drake Pintail - a scarce bird here. After my scan I was looking at some bare mud next to an area of reeds and thought "that looks nice for a crake". As I was thinking this, a Moorhen suddenly flew and flushed a rather small crake-like bird. I thought it was going to be a Water-rail until I saw it turn its head and I saw a short stout yellow bill and white spots. It was a Spotted Crake! My daydreaming had come to fruition! A long awaited lifer!

With southerly airflows set to creep in during the week I'm expecting lots of new arrivals and hope to report back with some interesting birds, and pictures if I'm really lucky!

In non-avian news - I had a maximum count of 5 Vagrant Emperors in and around Cal Tet. I also found a lovely patch of real wild orchids (no protection like those wired off within the reserve itself). I had a good look and could only see one species: Early Spider Orchid, of which there were about 20. 

I saw several Green Hairstreaks, which were Llobregat ticks also. 

Reptiles of Delta Llobregat

One of the novelties of living in a warm country is the increased biodiversity of reptiles, and Delta Llobregat has its share, with a total of 13 species (give or take) present in the reserves. You can view the official list here.

Having had a very close encounter with a 5+ foot Montpellier Snake the other day at Cal Tet, I thought it would be a good time to summarise and reflect upon my own reptile encounters in the delta  since arriving last May. Out of this 13 species I have seen at least 8, plus an additional species not on the list.

Montpellier Snake, Sabogal boardwalk, Cal Tet

A total of 7 lizards & geckos occur in the reserves, namely; 

1. Large psammodromus Psammodromus algirus (frequent)
2. Spanish psammodromus Psammodromus hispanicus (scarce)
3. Spanish Wall Lizard Podarcis hispanica (scarce)
4.  Moorish Gecko Tarentola mauretanica (frequent)
5. Mediterranean House Gecko Hemidactylus turcicus (very rare)
6. Ocellated Lizard Lacerta lepida (very rare)
7. Slow Worm Anguis fragilis (scarce)

Large psammodromus is a common sight around Cal Tet in the summer, especially in the mornings along the boardwalks leading to Sabogal & Cal Tet hides, where they scamper out of harms way as one walks past. Presumably, they use to heat from the wooden boards to warm up first thing. The most obvious feature of Large psammodromus is its comical long tail which is often the last thing you see disappearing into the undergrowth as you walk along the paths in summer. 

Large psammodromus, Sabogal boardwalk, Cal Tet

Large psammodromus (with skeletal deformity), Sabogal boardwalk, Cal Tet

Again on the same board walk, Spanish Wall Lizard is a fairly common sight. They are however, very variable and I am still having difficulties separating some individuals from Spanish psammodromus.

Spanish Wall Lizard, Sabogal boardwalk, Cal Tet

Spanish Wall Lizard, Sabogal boardwalk, Cal Tet

Moorish Geckos are quite commonly seen basking in the sun in the early hours too, more often on rocks. For this reason, the rocky boulders near Ca L'Arana & the nearby abandoned rocky buildings are my favourite areas to view the species, often in double figures at the right time. I also see them regularly on the boardwalk along the Bunyola ruins. I have yet to find a Mediterranean House Gecko anywhere in the reserve, but I'm going to try this summer. Interestingly, if you look closely in between the toes of the geckos, you can usually see some bright red dots. These are actually mites, and can bee seen in both pictures below, if you look closely.

Moorish Geckos, Ca L'Arana

Moorish Gecko, Ca L'Arana

I have also yet to see an Ocellated Lizard in the delta, and may not as the species is noted as being "very rare". I have had the fortune of seeing this species further north near Olot, and was very impressed with it, what with it's bright green colour with vivid blue spots, and its large size, reaching a maximum of 3 feet!

Ocellated Lizard, Northern Catalunya

Ocellated Lizard, Northern Catalunya

Next on the list are the turtles. There are only two species listed but I suspect there are more. Unfortunately there is a vast problem with non-native species here and I regularly see very large numbers of Pond Sliders Trachemys scripta (an american non-native), consisting of 3 subspecies:

1. Red-eared slider
2. Yellow-bellied slider
3. Cumberland slider

Red-eared Slider, Delta Llobregat

Yellow-bellied Slider, Delta Llobregat

Whilst looking for Mediterranean Pond Turtle last summer, I took the above photos of the numerous Pond Sliders, and amongst them I saw a different looking turtle, which, after a little research proved to be another American non-native species: Mississippi Map Turtle Graptemys pseudogeographica kohni, a species commonly kept in the pet trade, so presumably this is an unwanted pet that was fecklessly released into the reserve to join the hoards of non-native sliders.

Mississippi Map Turtle, Delta Llobregat

Mississippi Map Turtle, Delta Llobregat

Unfortunately the native Mediterranean Pond Turtle Mauremys leprosa is rather rare but with perseverance it can be seen. You just need to spend time scanning water-bodies where turtles are swimming or basking. Sometimes you can just get lucky, as was the case when I took the photos below, when one crossed the path in front of me at Cal Tet.

Mediterranean Pond Turtle, Cal Tet

Mediterranean Pond Turtle, Cal Tet

Finally, there are the snakes, of which four species have occurred in the delta. These are:

1. Ladder Snake Rhinechis (Elaphe) scalaris (scarce)
2. Montpellier Snake Malpolon monspessulanus (frequent)
3. Viperine Water Snake Natrix maura (frequent)
4. Grass Snake Natrix natrix (very rare)

I have seen 3 out of 4 snakes in the reserve, with the missing species being Grass Snake, which isn't a surprise, as it is listed as very rare. 

The first snake I encountered in the delta, was a rather large Ladder Snake, inside one of the semi-ruined buildings at the back of Ca L'Arana beach. It really took me by surprise, because at the time I wasn't used to seeing snakes, having recently moved from Ireland, and this was also a rather large specimen. I was able to see it very well as it really didn't seem to be bothered by my presence, or perhaps it didn't see me too well, as one eye was missing and the other had a thick white layer of dry skin over it. This species is non-venomous and preys upon, birds, small mammals and lizards and often enters ruined buildings in search of said prey items, as was the case here. 

Ladder snake, with one eye missing, Ca L'Arana

Dry skin partly clouding the other eye.

 

Ladder Snake with distinctive black stripes.

I have seen Montpellier Snake well twice in the delta, both in exactly the same location, the Sabogal boardwalk, at Cal Tet. The first individual was a juvenile sitting atop of the boardwalk last summer.

Juvenile Montpellier Snake, Sabogal boardwalk, Cal Tet

The second occurred this week when I flushed a large adult. It happened so fast; I only saw the tail disappear into the undergrowth. On my return loop I had the idea to check, as unlikely as it would be, to see if the snake had returned to the same spot, after I had passed, to continue basking in the sun. I approached very slowly this time and when I reached the area I couldn't see it and assumed it had moved on. This was until I focused a little better and realised it was right at my feet and was staring right at me, as is evident in the following first image I took:

Montpellier Snake - death stare! Sabogal boardwalk, Cal Tet

For the following 10 minutes I sat very close and really admired this snake in detail. It was really stunning, and big, at about 5-6 feet. I noticed it had some blood staining at the back of the head, and this added further to the menacing, but beautiful look of this incredible animal. I wonder did the blood come from a previous meal, or perhaps a struggle with a rodent, or even another predator? I later discovered that this snake is mildly venomous, but as far as I know it isn't really a threat to humans. 

To date I have only seen one Viperine Water Snake, and this, living up to its name was seen swimming in an area with Perez's Frog (a principle prey item), in Remolar Filipines.

Vagrant Emperors & Perez's Frog

As well as lots of migrant birds passing through Llobregat right now I have been seeing some equally interesting invertebrates, amphibians, reptiles, plants and more. Every day I visit the reserve I see something new or at least have the chance to photograph something new. That's what I love about Catalunya. The weather is always great and there is always something to see. 

My list of non avian highlights from the past week are as follows:

1. Finding 3 Vagrant Emperors Anax ephippiger, 2 of which were copulating, with the female ovipositing. 
2. Finally managing to see and photograph Perez's Frog Pelophylax perezi, which I have been hearing (only) since last summer.
3. Finding & photographing a Peacock Aglais io (butterfly) which is very rare in Delta Llobregat, with only a handful of previous records.
4. Discovering Mallow Weevils Lixus angustatus, personally, for the first time.

1. Vagrant Emperor

Having had frustrating views of Vagrant Emperor the previous week, obtaining a terrible record shot; it was rewarding to find 3 examples which performed much better. Whilst they didn't land close enough for a really nice picture, they flew in a somewhat predictable pattern and allowed me to view the species well for the first time in my life. I also managed some better, but still not great, record shots. 

This species is a rare but regular migrant from sub-Saharan Africa to the reserve, and from what I can tell, early spring and late autumn are good times to see the species here. Not many dragonflies are on the wing here at the moment, and thus checking any large dragonflies has resulted in me seeing 5 Vagrant Emperors over the last week or so.  

Before recently, the only obvious morphological difference I knew of between Vagrant & Lesser Emperors, was that Vagrants have brown eyes and Lessers have green ones. It has since been pointed out to me that the blue "saddle" is a deeper blue on Vagrant Emperors, and only extends half way down the body, with the blue extending downwards much further on Lesser Emperor. All of the aforementioned differences can clearly be seen in the two pictures beneath. 

Mating Vagrant Emperors, Delta Llobregat, 2019

Mating Lesser Emperors, Delta Llobregat, 2018

One other feature I learned of, is that Vagrant Emperor has paired light spots on S8-10, whereas the same segments on Lesser Emperor are plain in comparison. These spots are illustrated in the below images, and can be compared to the plainer end segments of the male Lesser Emperor above and left. 

2. Perez's Frog

Having heard this mysterious frog all throughout last summer and autumn and again the last few weeks I was really determined to see one of the creatures responsible so I started to check small clearance pools along the track to Cal Tet. I saw a splash in one as I approached and was disappointed that I didn't approach more carefully, but was then delighted to see that there was still another sitting atop of some flotsam. I managed to get extremely close and was really happy to produce the below image, of what has been to me an extremely elusive, almost mythical animal in the reserve.

Perez's Frog, Delta Llobregat

Perez's frog is native to southern France, Portugal and Spain and is widespread and common (though not necessarily easy to see!). Its name in Spanish is  rana común  which literally translates to "Common Frog". See below for a recording I took in the reserve, of several call individuals.

3. Peacock

Whenever, I go to the delta, I always pay attention to the butterflies that abound the tracks and trails, & I think I have seen around 25 species over the last year. When I came across a Peacock on the path a few days ago, it was exciting as it was a new butterfly for me in the delta. However, having spoken to Ferran Lopez on the matter he confirmed that it is very rare there with only a few previous records, which was quite cool! This makes sense when you look at the European distribution of the species, with its southern limit occurring around the Barcelona region. I was lucky to get very close to it with the sun to my back.

Peacock, Delta Llobregat

This was not the only new butterfly added to my Llobregat list, as I also recorded two Bath Whites feeding on what appeared to be some kind of vetch in the arid sandy areas behind Ca L'Arana beach. Unfortunately they were quite distant allowing for only record shots, but they were beautiful, regardless.

Bath White, Ca L'Arana, Delta Llobregat

4. Mallow Weevil

Walking back to my bike along a riverside track, a strange shape on one of the large Mallow plants caught my eye. Every time I tried to get a closer look its body would turn around the stem of the leaf it was gripping to, so it kept itself concealed from me. I eventually saw it well and realised it was a big weevil species with a long snout. After googling "weevil" and "mallow" I found the suspect - Lixus angustatus. I soon discovered the animal to be quite common throughout the reserve on large Mallow plants. 

Lixus angustatus feeding on Mallow, Delta Llobregat

 

The final nice  invert' came in the form of a moth, more specifically, Puss Moth Cerura vinula. I saw this clung to a fence post right at the entrance to Cal Tet, clearly having chosen this as a resting place after its nocturnal activities. This is the first time I have seen the actual moth of this species, having previously seen the colourful larvae in Ireland a number of times.

Puss Moth, looking furry, Delta Llobregat

Last but not least, although it's a shame that it was dead, was this snake species found at the side of the road near Can Dimoni. Whilst I'm not fully certain, it appears that this is a Viperine Natrix maura, although, I could definitely be wrong!

Snake sp, Can Dimoni, Delta Llobregat

Migration Picking Up!

It's been a great week at Delta Llobregat, with  spring migration becoming quite evident, featuring impressive numbers of some really nice species. The shift towards summer has been quite apparent these last few days, and it's been quite exciting. A lot of work has been done to improve habitat for waders (ploughing & flooding) and it's looking fantastic.

Cal Tet Lagoon & Marsh, as well as the pine wood of Ca L'Arana

Throughout the week there have been good numbers of Chiffchaffs & Song Thrushes, as well as small groups of Chaffinches, and scatterings of Black Redstarts & Robins throughout. Barn Swallows & Sand Martin have been present in passing groups throughout the week, with the latter being a patch tick!

The first Redshank appeared, with 8 present around Cal Tet on Thursday. There was also a single Black-tailed Godwit, as well as several Spotted Redshank, a few Ruff, some Dunlin, lots of Little Ringed Plover & Green Sandpipers & the usual lone Oystercatcher. 

Migrant Ruff & Spotted Redshank - Cal Tet Lagoon

Black-tailed Godwit, Remolar Filipines

There have been good numbers of Yellow Wagtails coming through, with a high count of approx' 30 at Cal Tet on thursday. So far I have been able to identify two subspecies (Iberiae & Cinereocapilla). 

 

Iberian Yellow Wagtail (ssp Iberiae)

Italian Yellow Wagtail (ssp Cinereocapilla)

There has been a very impressive movement of Glossy Ibis, with numerous large flocks traveling north. The largest of these flocks held a minimum of 73 birds, which circled and landed in front of the hide at Remolar Filipines. I noticed birds regularly stretching out wings, keeping them outheld for some time. I assume this is to recover tired muscles after long migratory flight. Whatever the reason it was interesting to see multiple birds doing this throughout the flock, at a given time. 

Migrant Glossy Ibis, Nelson Mandela Bridge

73 Migrant Glossy Ibis, Remolar Filipines

Migrant Glossy Ibis wing-wtretching

Another impressive sight was that of a flock of at least 17 very vocal Garganey at Cal Tet. I had only ever seen singles of this species in the past and had never heard one. The call is amazing! Unfortunately the wind was far too strong to get a recording, but I would love to record it in the coming weeks, if I get the chance. 

Male Garganey, Cal Tet Lagoon

Part of a flock of 17 migrant Garganey, Cal Tet Lagoon

Other highlights include an adult Spoonbill (patch tick), which is a scarce migrant, and finally adding Corn Bunting to my Llobregat list, with several singing birds around Can Dimoni.

Adult Spoonbill, Nelson Mandela Bridge.

As well as migrant birds, other heralds of spring included numerous interesting invertebrates, plants, amphibians & reptiles, but these will be covered in a separate post.