Harbour Seal Decline Project

Last week I was invited to give a presentation about the harbour seal decline project to the Orkney Field Club. The club is a local charity which focuses on enjoying, understanding, recording and conserving Orkney’s flora and fauna. The club very kindly organized the venue and made sure to spread the word around its members. It was a great evening with a great turn up of over 30 people!

I presented some background information on grey and harbour seals and their current population trends, and then went into the details of the research conducted in Orkney and other areas of Scotland to investigate the decline in harbour seal numbers.

Showing the movements of the 10 seals that were tagged in back in May was a highlight of the evening, with surprised faces among the audience of how far or close has each seal been moving over the last couple of months.

We also talked about the use of photo-identification data to estimate birth and survival rates of harbour seals, and how this information is useful to assess the status of populations. We obviously dedicated some time to harbour seal pups, now that we are reaching the peak dates of pupping season in different regions across Scotland.

After the talk there was an open session of Q&A which was filled with interesting questions about the biology of harbour seals, the monitoring of populations and the potential causes of the observed decline in Orkney and other regions. Overall it was a fantastic evening, and I am very grateful to the Orkney Field Club for allowing me to join them for a seal chat. As the project will continue over the next few years, I am hoping I will have the opportunity to meet again next summer.

Written by Monica

Pupping season is well underway in Orkney. Haulouts are filled with activity and movement, as mum and pup pairs keep showing up. This has also gotten the attention of seagulls and great skuas, who keep a close eye on the seals and are very quick at taking the opportunity of a placenta laying in the seaweed or on the rocks.

Pups can be seen fast asleep, resting, or suckling but are also extremely active, going into the water for a swim and exploring the new surroundings as well as the new neighbors! Mum and pup pairs interact by touching nose to nose and calling each other, and young pups are often seen riding on their mum’s back in the water. In general mums keep a close eye on the pups, following them into the water when the young ones decide it’s time for a swim!

Pups are regularly seen suckling, either on dry land or close to the water. But it’s not always a straight forward business, especially when mum decides to rest on a rather small rock for the both of them to settle. Check the next video:

The exploratory visits by the new pups into their surroundings and to check on the neighbors are often received with simple curiosity by the juvenile and adult seals when presented with a tiny pup. Other times though, they cause trouble. Mums may quickly intervene to put an end to an unwelcome interaction between their pup and other seals, but other times they just keep an eye from the distance.

Pregnant females are especially not very happy to have a small pup approaching them, and they make it very clear to the newcomer by growling and moving the fore flippers to keep them away. In the video below you can see a young pup approaching the seal on the right, who is pregnant, while its mum, the seal on the left, observes the interaction close by.

Written by Monica

Over the past five and a half weeks I have been surveying harbour seal haul outs along the East Kintyre coastline north of Campbeltown – I thought it was about time I checked in with a blog post.

One of the haul outs I have been surveying is immediately outside my accommodation and the seals are present in the area pretty much all day – hauling out at low tide and at high tide. At high tide, they haul out on a rough rocky breakwater only a few metres from the shore. Due to the proximity of the seals, I am able to get some high quality photographs to help with identifying the seals – see the following photograph showing the seals hauling out at high tide (note the poor injured individual second from the front).

The northernmost haul out has seen the highest number of harbour seals – I counted 66 seals on one visit. The southernmost haul out is only exposed when the tides are particularly low but it was here that I been observing the largest number of obviously pregnant seals.

As pupping season seemed to have started everywhere but here, I was keen to spot my first pup of the season. As the tide was low enough today, I decided to get up early and venture to the southernmost site for low tide this morning. My early morning was well worthwhile as I did indeed observe my first pup of the season (see cute photograph of mum and pup).  Hurrah!

Written by Craig

As pupping season advances, seal haulouts are filled not only with mum and pup pairs, but also with various displays from harbour seal males, who are getting ready for mating season. Seals can be often seen ‘porpoising’ and swimming very fast just under the surface, close to the haulout. Seals are also observed splashing the water with their fore flippers, which generates loud sounds, getting the attention of the other seals around. Pairs of seals may be seen rolling together near the surface in a type of gentle play-fight, and individual seals quite often do energetic head swinging back and forth while holding bits of kelp in the mouth. And there is a lot of growling and snorting among seals.

These displays can escalate into more intense fights between seals. A few weeks ago, before the first pups were born, I witnessed a fight between seals at one of the sites. As I was ready to start taking pictures, two seals engaged into a very intense fight just by the water edge, which involved a lot of fore flipper slapping and splashing, rolling, biting, growling, snorting and energetic throwing of kelp. The interaction lasted about 3 or 4 minutes. As you can see in the video below, one of the two seals has a yellow flipper tag in one of her hind flippers. It turns out this is a male we captured earlier in the season. I am afraid he did not choose the winning stick this time… I was very impressed by the intensity of the fight, something I don’t think was shared by the rest of the seals at the haulout, who did not seemed to be very disturbed by all the activity around them.

And a couple of days ago, there was another interesting interaction at the same site by another two seals. This time it was shorter, but preceded by a much longer exchange of growling and snorting, as well as fore flipper slapping of the water.

Written by Monica

Pups have finally arrived at Loch Dunvegan on the Isle of Skye! Three pups have been seen in the last few days but hopefully many more will be born in the coming weeks. The boatmen, Colin and Adam say that over 50 pups may be born in the Loch in a good year.

My role is to go out with the Dunvegan Castle boatmen twice a week and photograph the seals hauled out on the skerries and islands in the Loch. Ideally I try to get photos of the left and right profiles of each seal and these are later identified and numbered. The aim is to create a catalogue of all the seals and especially to record the mothers and their pups. Over time this will allow us to look at fecundity and the reproductive success of the seal population in the loch.

As the seals are so used to the castle boats they allow us to get very close to them without being disturbed and it is fantastic to observe them at such close quarters.

One interesting observation is the wide range of colours of the seals from white to grey or dark brown. One instantly recognisable seal is an orange female known locally as Morag. Her head and shoulders have a bright orange pelage unlike any of the other seals in the Loch. Colin, the head boatman has known her for over 20 years and says she has had many pups in that time. One of the yearling seals (last year’s pup) also has an orangey fur colour, although not as intense as Morag.

The orange coloration is thought to be caused by foraging in sediments containing high levels of iron oxide, which gets deposited on the seal’s hair. These orange seals are quite a common sight in many areas, for example in the Thames Estuary , and it has been observed in other species of phocids such as bearded seals.

I am very grateful to the staff at Dunvegan Castle and especially the boatmen for allowing SMRU to make this study as it is a privilege to get so close to these amazing wild animals.

Written by Andy

Pupping season has finally started in Orkney! Over the last week, while visiting haulouts to count and take photographs of the seals, I have seen the first new pups of 2016! These first pups of the season made it a bit difficult to be spotted as the mum and pup pairs were located at quite isolated haulouts far from any dry land, but I managed to get enough pictures to identify the females.

Harbour seal pups are born with their adult coat, which is very dark though already with the characteristic spot pattern. Pups can swim as soon as they are born, which means that females can give birth at a site regardless of whether it may get covered by water with the incoming tide. Pups are frequently seen at a haulout sleeping or suckling, but also swimming in shallow waters; and as days and weeks go they will gain more independence from mum and adventure further.

A visit to one of the haulouts a few days ago brought a very welcomed and nice surprise, as one of the seals that we tagged earlier in the season showed up with a tiny new pup! More precisely, this female had traveled down south to the Moray Firth where she spent a good month and a half before heading back to Orkney. We hoped she would be back for pupping and so she was! You can see her gorgeous new pup below.

There are still a lot of very big females at the haulouts, so we expect the number of pups to increase in the upcoming few weeks. In the Moray Firth, our colleagues from the University of Aberdeen Lighthouse Field Station are also in full pupping season, with one of the pups being born to one of their well-known females. Meanwhile in Isle of Skye, Andy has still to see a pup, although the Dunvegan Castle Seal Trips have reported their first pup of the season already. Hopefully Andy gets to photograph pup and mum over the weekend on his next visit.

Written by Monica

Over the last month I have been very lucky to join members of the Orkney Islands Sea Angling Association and their boat ‘Welcome Home’ during a couple of competition trips. On both trips, we left the harbour in Stromness early in the morning, with the sun shining, and headed out of Scapa Flow towards the west, with amazing views over Graemsay and Hoy.

We stopped at various locations to fish, all located west of Orkney, in an area close to where two of the seals that we tagged earlier in the year have been on their trips.

Once the competition had ended, Roy and the rest of the crew got onto cleaning the fish that had been caught. Each fish was measured, to estimate its weight later on, the species noted down, and the guts from each fish were stored in plastic bags. Once back at SMRU, these stomach samples will be analyzed for prey quality. Also, the list of species caught, which for both trips included ling, cod, haddock and torsk, gives us an idea of which fish species are available to the seals in different locations around Orkney.

The trip also offered a great opportunity to observe several species of seabirds, including great and arctic skuas, fulmars, great black-backed gulls, puffins, guillemots and razorbills. And we even saw a harbour porpoise! The fulmars, despite their smaller size, seemed to keep the great skuas in place when bits of bait or fish were thrown into the water.

At the start of May I headed up to Isle of Skye to meet with Andy, who is going to be in charge of conducting the photo-ID trips at Loch Dunvegan this summer. To do so, we are collaborating with the Dunvegan Castle seal boat trips team, who run regular boat trips to see the seals (mainly common seals) hauled out at the nearby small rocky islands of Loch Dunvegan. The traditionally built clinker boats can get within a few meters of the seals without disturbing them as seals are used to having them close by.

We arrived at Dunvegan Castle (which is the oldest continuously inhabited castle in Scotland!) as doors were opening to the public, and headed down to the pier below the castle, where Colin, one of the boat skippers, was waiting for us. We were very lucky with the weather and seemed to catch the only dry weather window of the long weekend as we made our way to photograph the seals.

Getting so close to the seals means the quality of the photographs is exceptional, so we expect lots of great data coming out of Loch Dunvegan this summer. Andy will go out on the boat a couple of days every week and photograph as many seals as possible as the boat goes around the skerries. On a single trip he may encounter over 100 seals, which means long hours in front of the computer trying to identify and match each seal based on the pelage pattern.

As we approach the end of May we are getting closer to the start of the pupping season for common seals. It is still too early to see any pups, but we can already see big females that look very pregnant. Check this seal on the photograph below, with that extra belly resting in the water. Hopefully we will see her with a new pup in a few weeks.

Written by Monica

2016 fieldwork season is officially open! A team from SMRU headed up to Orkney at the start of April to deploy telemetry tags on harbour seals. Once deployed, the tags will send back information on the location of the seals, both at sea and ashore. The tags, which are harmlessly glued to the fur at the back of the head, will fall out in the late summer when the seals start their annual moult. Meanwhile though, they will inform on each seal’s whereabouts and their usage of the different haulouts, information that we can then use to direct our photo-identification effort during the summer pupping season.

I headed up to Orkney a few days in advance of the rest of the team, to check on several haulout sites known to be used by seals based on data from the aerial surveys. And to my delight, there were seals! I conducted counts at different sites while taking the opportunity to collect some pre-pupping season photo-identification data.

Once confirmed that there were enough seals the rest of the team joined me with boats and supplies. We had some spectacularly sunny and calm days but also some days with high winds and even snow! It was quite a surprise to see the hills of mainland Orkney and Hoy covered in white.

Despite the weather, we successfully tagged ten adult harbour seals in the area of Scapa Flow. A part from deploying the tags, we also collected individual covariates on the captured seals before releasing them (e.g. sex, age, condition, pregnancy status, health status, and toxin exposure), to investigate their effect on vital rates estimates.

As soon as each of the tagged seals gets into the water for the first time, the telemetry tags start recording the location of each animal as well as details of their dives while at sea. This information is sent back to SMRU when the seal is close to the coast within mobile phone coverage, using Vodafone’s latest machine-to-machine (M2M) technology. After that it’s just a matter of keeping an eye on the daily progress of the seals as information on their location is being delivered to our computers!

Written by Monica