Stranding season continues..

It seems to be a season of many strandings. On Wednesday this week a humpback whale was reported to us by Neels Dreyer to be stuck in shallows of the harbour in front of the fishing factories. The NDP team and John Paterson (Albatross Task Force) responded promptly and got on site to find several divers from Walvis Bay diving already in the water trying to guide the animal out to sea. After a little discussion with the TunaCor security officers to assure them we were there on legit business, John, Gwen Penry and I got our wetsuits on hopped in the water with the divers to help with the rescue attempt.

The whale was clearly unwell, covered in cyamids (whale lice), had a broken dorsal fin (probably from hitting into the jetty, it definitely wasn't a propeller cut) and was clearly disoriented, swimming at an angle, holding its head up and only going in circles. With much pushing we occasionally got the animal out of the shallows but it kept turning back to come lie on its belly. We attempted to the tow/guide the whale out of the shallows with help from the Walvis Bay diving boat, but although it got out a little way, it again came back.

The WBD boat had to leave but we got in two more boats from Mola Mola Tours and Henning DuPlessis (a local oyster farmer). These larger boats were more successful at pulling the whale further out of the jetty area, and eventually managed to get it past the moored ships. With some great driving by Rudi Hass and Eddie of Mola Mola and Henning - they managed to keep the whale from turning back to the shallows and guided her out in the deeper central bay area (last photo).

Once in the deeper water the whale paused to reoriented it self and seemed to wake up and head off strongly northwards. We were all hopeful that it was going to make it but unfortunately, on Thursday, the whale was reported re-stranded on the west side of the bay near the pump station.

The decision was taken at this point to let nature take it's course. Strandings are sad, but natural events and you can only perform so many rescue attempts (which are quite stressful for the whale) before admitting defeat.

I've put in some photos below, most taken by Lucille Chapuis, (one of our July interns) of the rescue operation in the harbour.

A big thankyou to Walvis Bay Diving, Mola Mola tours, Henning du Plessis and Tunacor for their help.

By Caroline Budden.

Hello! My name is Caroline and I am currently an intern at the Namibia Dolphin Project. I arrived here on the 1^st of July from the UK. The view as I flew from Johannesburg to Walvis Baywas beautiful and consisted of miles of desert as far as the eye could see. I was met at the airport by Simon and after meeting the other interns and staff, I was soon feeling settled in and started learning how to grade dolphin photographs. This is important as only high quality photos are used to identify individual dolphins. The next day, on land survey duty, I caught a glimpse of my first bottlenose dolphin, which surfaced about 10m from shore. After teasing us with two short appearances, it then promptly disappeared. On my next land survey a few days later, we came across a whole group of bottlenose dolphins close to shore. We watched them wave riding, took as many photographs as we could and spent the next few hours tracking them from the beach to monitor their social interactions and general behaviour. This proved to be more difficult than it sounds - you don’t realize just how fast they can swim unless you are running alongside, trying to keep up with them!

On our day off, myself and the other interns went kayaking with wild seals at Pelican Point. The seals were adorable and were very intrigued by us and our brightly coloured kayaks. They were constantly swimming over to take a closer look and there were even a few attempts to steal our paddles! We saw a number of jackals as we drove through the desert and were amazed to witness a stand-off between a jackal and a fully grown seal. The jackal won the fish prize in the end but the seal didn’t give up easily!

While out on the research boat we encountered a whole group of Heaviside dolphins, inccluding two mothers with calves. I will never forget the sight of a baby calf swimming alongside the boat right beside me. However, the highlight of my first week here has to be the sight of a humpback whale surfacing about 5m away from the back of our boat. The noise of it blowing out as it surfaced made everyone on board jump with shock, especially as we were all expecting it to come up about 500m away in a completely different direction. I have had so many incredible experiences here in just a week and I am eagerly looking forward to the next few weeks!

If you're on Facebook, check out the Namibian Dolphin Project page for more photos from out current field season.

Here are a few of the small humpback whale that stranded alive near the desalination plant north of Swakopmund last week. It died soon afterward we first saw it, and we returned to collect some samples from the animal for further study.

The blog is going to start filling up again! We haven't had much internet at the house where we base the office, and it's been a pretty hectic start to the season. Dolphins coming and going as usual, but we've got the hydrophone in at Sandwich Harbour again (Thanks to Ingo of Pelican Tours for lending us his dinghy!) and we've seen at least two known Heaviside's again, including the animal that was injured so badly last season by a boat propeller - and he's completely healed (you can just see the scarring on his body below)!

This season we're a much bigger team than normal and we've got 5 interns working with us here through Oceans Research. This has allowed us to start a new project collecting data from shore on the bottlenose dolphins (so there is no bias from the boats at all), as well as get more info from the tour boats themselves and get that back log of data under control! We've also had a few strandings and well, there's lots going on. I'm going to let the interns put it in there words from here on:

Namibian Dolphin Project by Melanie Ngo

The interns arrived on the 1^st of June and I am one out of the six that get to experience this wonderful opportunity. For the past few weeks, we have done a lot of work on shore and on the water in Walvis Bay, Namibia. We are having an amazing time with the Heaviside dolphins and the bottlenose dolphins each time we are at sea and on land. It is and will always be a thrilling excitement every time we encounter these animals, no matter how many times we have seen them before we enjoy their company out at sea. When I see the expression on Simon’s face every time we spotted the dolphins, it reminds me of the face kids make when you bribe them with candy and he has been working with these animals for a couple of years now.

We have taken pictures of the Heaviside's and bottlenose dolphin’s dorsal fin for photo ID, observed their behavior in the water and on land, and observed the number of birds and bird species in certain areas on the beach to look at the impact of beach users. Most of the time, the dolphins are very friendly, socializing with us and each other, they were jumping and spy hopping, swimming alongside the boat, bow riding, swimming underneath and around the boat, overall they are having a good time in their own home. There were a few days we did not go out on the boat due to the weather, but that did not stop us from doing work around the office. We have had long days out on the boat and on land, we’ll come back exhausted, but love every minute of our time with the dolphins and that keeps our energy up for the rest of the day.

Melanie:

Bottlenose dolphins double their known range!

Dr Jean Paul Roux from the Ministry of Fisheries, who we collaborate with down in Luderitz sent me some photos they captured from shore in April of a group of bottlenose dolphins in Guano Bay (the main Heaviside's dolphin concentration area in Luderitz).

Although they occasionally see bottlenose dolphins down there, they tended to be very poorly marked (undistinctive) animals, and have always been assumed to belong to the offshore stock of bottlenose dolphins (which live in the open ocean off the continental shelf, and don't mix with the local population). The Walvis Bay population has a known range from Sandwich Harbour to Cape Cross (only about ~250km along shore), but with observer effort very low north and south of these points, we assumed they probably did range a bit further than that, there was just no one there to see them.

So this sighting was really exciting as we now have photographic proof of 'our' population of bottlenose dolphins in Luderitz, about 400km south of the known limit of their range! There were about 12 animals, several well marked ones including some of those tagged in the lagoon in 2009 and some of the mother-calf pairs.

We'll be back in Walvis Bay at the beginning of June to work all of June and July and plan to spend some more time in Luderitz in August. This will give us a chance to see if these animals were simply on a summer holiday trip and have come back to Walvis Bay, or if they have 'permanently' emigrated.

Slow on the updates recently. We wrapped up the season in Walvis Bay and left town on the 26th March as I had to give a talk up in Windhoek at UNam. I've never been there before, it's quite a small university compared to Pretoria or UCT, but a nice campus. The talk went well, there was small, but interested crowd who asked lots of questions, which is always nice.

Then moved on down to Luderitz to go service the hydrophones down there and collect some skin samples for analysis. I couldn't have done it without the help of Jean Paul Roux at the Ministry of Fisheries. We took out their research ship the Anichab (actually it's "!Anichab", but apparently if you mispronounce the initial click represented by "!", you turn it into a rather rude word, so most folk err on the side of the English pronounciation and just start with the A...). It was a good few days (although pretty windy the whole time), and great having a whole ship and good crew to help with everything. Hauling the hydrophone moorings is a pleasure with a winch, and we got them cleaned up and put back in in no time. I put down another hydrophone just at the northern edge of the Lighthouse bay, to replace the one in Guano Bay that is still AWOL. Biopsying was slow work as the weather didn't play along and the dolphins weren't as super friendly as they usually are in Luderitz, but we got there in the end.

Exciting sighting of the week - 2 minke whales! Apparently there are two or three in the bay which have been around and seen on a weekly basis since December by Heiko Metzger (Zeepard Tours). I've put in a few photos below of hauling and cleaning the hydrophones and the minke whales as seen from the ship and one of JP's pics of me and the !Anichab crew out in the little dinghy trying to get biopsies.

More exciting news - JP just emailed me the other day to say that a few bottlenose dolphins had been spotted in the bay and they all had large distinctive markings. The Walvis Bay population isn't supposed to range so far south (it's ~400km from Walvis), and bottlenose dolphins that have been seen there previously are thought to be vagrants from the offshore populations. However...photo ID will tell and hopefully the Luderitz locals can get us some usable photos.. i'll keep you informed.

Busy times here. We were out to sea almost everyday last week and had a great run of good dolphins and good weather. Luckily(?) that's turned now and it's been quiet and rather choppy out there the last two days, so we're taking today off to catch up a little. Season is drawing to a close and there's still lots to do and summarise.

The good news - we have twice seen the injured dolphin since the original report a few blog posts ago. He ('it' really as we don't know it's sex) still bowrides the boat, but most importantly is healing amazingly well. If you click on the images it opens a slightly larger version. Compare the two photos below to the open wounds of the original photos. I'm really quite astounded at how well these wounds have healed.

I sent an email around to all the tour operators about this sighting and I think it really brought it home to them that as the people out there every day, the responsibility for the animals lies with them. They have all been really good about not reverse bowriding with the dolphins and letting them determine the space use a little more.

Jeff Slater from Cape Town has joined me up here for the month to help out on the boat with driving and taking photos. Jeff is considering a career in marine biology and I'm doing my best to show him both sides of the coin - the fun side on the water, and the real work which involves sitting behind a computer for hours on end processing data, writing grant applications and updating the blog. I really ought to put up more pictures of empty seas on misty days, freezing cold mornings and dimly lit offices with flickering computer monitors - just to give a more rounded view of what we do out here :) I'd also roped in Edith Mertz, to help me out for a few weeks. Edith is a Master's student of mine who's investigating the interactions between cetaceans and a fin-fish farm that is being developed in Mossel Bay. It's something we also touch on here in Namibia here there are a large number of oyster farms in the bay. Now that we have four seasons of spatial data from Walvis, it's really interesting looking at the variation in habitat use between seasons, and what the implications of that are for coastal development or trying to make restricted or protected areas. Edith's work is described on the site below:

http://www.oceans-research.com/marinescienceprojects/mosselbaycetaceans.html