|Namibian chicks set out on their first journey|
Seven naturally-reared chicks have been equipped with PTTs and released in Namibia over the last two weeks. They have been at sea transmitting for several days. Find out where they are and read the PDF of the full story here.
|New paper: Survival of Rockhopper Penguins in times of global climate change|
Postdoc Katta Ludynia is co-author of a new paper that deals with the potential impact of climate change on rockhopper penguins. As a component of her postdoctoral research, Katta is a key member of a team of researchers at the Max Planck Institute for Ornithology, Radolfzell, Germany. This team conducts research on New Island, one of the smaller islands of the Falklands Islands. The motivation for this project is described in the Introduction: "On the Falkland Islands, Southern Rockhopper Penguins have been effectively protected since the 1950s and appear to be hardly affected by introduced predators. Nevertheless, the breeding population has declined from an estimated 1.5 million in the 1930s to 319 000 breeding pairs in November 2010. Currently, the conservation status of the southern rockhopper penguin is classified as 'vulnerable’ by the IUCN. Southern rockhopper penguins are good sentinels of change because they are less mobile than flying seabirds and mainly feed on low trophic level prey (e.g. krill, small fish and squid), which makes them more susceptible to changes in local primary productivity. Thus, Southern Rockhopper Penguins appear to be limited in the plasticity of their response to prey scarcity, an important criterion for seabirds as environmental indicators." In other words, the problem of introduced predators being the driving force for changes in population size are not true here, so any changes must be due to things going on in the ocean.
Dehnhard N, Poisbleau M, Demongin L, Ludynia K, Lecoq M, Masello JF, Quillfeldt P 2013. Survival of rockhopper penguins in times of global climate change. Aquatic Conservation: Marine and Freshwater Ecosystems. Currently published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/aqc.2331.
1. Anthropogenic changes in the marine environment and global climate change have led to population declines in several seabird species worldwide. Rockhopper penguins (Eudyptes chrysocome and Eudyptes moseleyi) have experienced a dramatic population decline, potentially linked to increasing sea surface temperatres (SST). Among Southern Ocean diving seabirds, rockhopper penguins typically occupy a low trophic level, and might therefore be expected to mirror climate-driven bottom-up changes to the food web sensitively and on a short time scale.
2. Using passive integrated transponders, survival rates of adults in a colony of southern rockhopper penguins (E. chrysocome) on the Falkland Islands were monitored over five consecutive years. Mean annual survival rates were in the range 84 to 96%.
3. These values are high compared with other crested penguin species and reflect the generally good conditions during the study period, when low SST prevailed. However, survival rates were lower in 2010, corresponding to very cold conditions. Curve fits showed a best-fit quadratic relationship between average SST anomaly and survival rates for the present data, aswell as for a data set including two additional years froma different study at Staten Island.
4. Results of this study suggest that rockhopper penguins survive best at SSTs that are lower than the average of the last four decades. In accordance with previously observed rockhopper penguin population declines, the present data suggest that rockhopper penguins are highly sensitive to changes in SST and their effects on the food web, a worrying perspective in times of global climate change. It seems likely that these changes could, in the long term, also affect population trends of other seabird species with similar ecological preferences.
5. The most promising conservation approach should aim at enhancing ecosystem resilience, mainly by reducing industrial fishing and oil exploitation. This would allow the currently over-exploited fish and squid stocks to recover, offering larger food resources to seabirds and other vertebrate species.
The pdf of the paper is available by email.
|Soon the Seli 1 will be out of sight below the waves, and it can be out of mind for penguins, because all the oil will be gone|
The wreck of the Seli 1 has been an eyesore along the coast of Table Bay near Bloubergstrand since September 2009. Three winters of oil leakage and the accompanying polluted penguins have followed. The Seli 1 was carrying a cargo of 30000 tons of coal and 660 tons of fuel oil and had 60 tons of diesel fuel on board. After its engines failed it was anchored in Table Bay. Strong westerly winds broke the anchorage before dawn on 8 September 2009, and drove the ship aground. The photo was taken soon after it came ashore - it looks nothing like this now. There was a big fire on board in June 2010 during dismantling operations, it has broken up in winter storms, and the most recent oilslick was in August 2012 when hundreds of penguins were oiled.
Weather permitting, next week it will have disappeared. It will still be there, but well below the surface. The aim is to flatten the three dimensional wreck into a two dimensional sheet of metal, but most importantly from the penguin perspective, to get rid of the last of the oil on board.
The City of Cape Town press release says: "A wreck reduction process in respect of the stranded Seli 1 vessel is, subject to favourable weather conditions, set to commence during the week of 11 March 2013. The wreck reduction, planned and undertaken through a multi-agency Task Team, is intended to strategically weaken the wreck structure and, with the help of the ocean forces, collapse it onto the seabed. Remedial and protective measures are being put in place by the Joint Task Team to manage and mitigate the release of any oils or pollutants, and the impact of this on the coastline and marine life. All risks with regards to oil pollution and the sensitive marine environment have been considered. Standby teams to respond to any oil pollution or oiling of seabirds will be in place, and SANCCOB and the Animal Demography Unit at the University of Cape Town have been engaged as part of the process. The complete collapsing of the wreck in this manner and the release of remaining pollutants under controlled conditions will likely remove all remaining negative impacts of the Seli 1 on our coastline."
The full press release is here.
Photo: Wikimedia Commons, Warren Rohner.
|Sudden death syndrome in Yellow-eyed Penguins in New Zealand – do you have any helpful suggestions?|
Since 21 January this year, 57 Yellow-eyed Penguins Megadyptes antipodes have been found dead on the Otago Peninsula in southeastern New Zealand.
As background reading, you need to know that the Yellow-eyed Penguin is endemic to New Zealand. Its IUCN threat status is "Endangered." There are two distinct sub-populations of Yellow-eyed Penguins. One breeds in the sub-Antarctic Campbell and Auckland Islands to the south of New Zealands's South Island. The other breeds on Stewart Island and other islands along the southeast coast of South Island, and also on the mainland on the Otago Peninsula.
The subpopulation along the South Island of New Zealand mainland is genetically distinct from sub-Antarctic populations. Therefore, penguins breeding along the South Island's coastline and its offshore islands need to be managed separately from those breeding on the sub-Antarctic islands. Population estimates assume a world population of 1700 breeding pairs, most of which belong to the sub-Antarctic subpopulation. However, the last comprehensive population surveys were made more than 20 years ago.
The South Island subpopulation is however monitored closely and fluctuates between 400–600 breeding pairs per year. The Otago Peninsula had 181 breeding pairs in the 2012/13 breeding season, is an important mainland population stronghold for this subpopulation.
Penguin consultant and expert Ursula Ellenberg writes: "Most of the 57 dead penguins were in excellent condition and experienced breeders. Dead birds had generally empty stomachs and often traces of vomit around their beak. In some cases blackish faeces stains were apparent. Post mortems and histological examinations showed no evidence of an infectious disease or trauma. Avian malaria has been ruled out though some virology testing is still being undertaken. Currently, acute poisoning possibly via biotoxins is being considered the most likely cause of death.
"The event is so far localised to the Otago Peninsula, on the south-east coast of the South Island, down-current from Dunedin city. Several weeks of warm and unusually calm weather may have resulted in the development of a harmful algae bloom (HAB). However, no other seabirds are known to have been affected.
"Because yellow-eyed penguins are almost exclusively bottom foragers we suspect any toxins associated with this event may have been ingested at the seafloor. Three freshly dead birds have been tested for a range of biotoxins, usually associated with HAB (e.g. domoic acid, brevetoxin, see below); but results all came back negative.
"We are keen to hear of any ideas as to what could have caused such rapid and unexpected deaths. Apart from biotoxins – can you think of any other toxic agents (probably of anthropogenic origin) that could be responsible and thus would be worthwhile testing for? Any feedback is greatly appreciated. Please send your suggestions to Melanie Young or Ursula Ellenberg. The biotoxins which we have tested for so far are domoic acid, epi domoic acid, gymnodimine, azaspiracid, okadaic acid, DTX-2, DTX-1, PTX-2, PTX-2 seco acid, yessotoxin, hydroxy yessotoxin, homo yessotoxin, 45 hydroxy homo yessotoxin, YSP toxin 1, Brevetoxin B2 and S-deoxy-Brevetoxin B2. In this picture, Mel Young examines one of the Yellow-eyed Penguins which died on the Otago Peninsula. Cause of death: currently unknown." (The photograph was taken by Peter McIntosh, of the Otago Daily Times.)
Here is a link for some Further reading.
|This disaster was ridiculously preventable: maritime report on the head-on collision between the bulk carrier Oliva and Nightingale Island last year in March|
On 19 March last year, the ADU website carried the following news item. It was among the first to break the news of this ornithological disaster.
'SAFRING ringer, Claudia Holgate, is currently aboard the M/V Prince Albert II, a cruise ship to the Antarctic. She reports: "On Wednesday 16 March 04h30 the cargo ship Oliva ran aground on Nightingale Island close to Tristan da Cunha. Because our arrival in the area was within 24 hours, our ship was informed by local authorities and asked to assist. On Thursday afternoon we conducted a rescue operation with our zodiacs to get the 10 remaining crew off the vessel. At 02h30 on Friday morning (yesterday), the ship split in half." This picture of the stricken vessel was taken by Claudia Holgate.
'Currently there is an oil slick spreading, and there are reports from Nightingale Island of Northern Rockhopper Penguins coming out of the sea covered in oil. Claudia reports: "The spill could not have happened at a worse place."
'The Oliva was a 75 300 tonne cargo ship carrying soya beans from Brazil to Singapore, and was carrying about 1500 metric tons of heavy fuel oil. The ship ran aground at Spinners Point, the NW corner of the island. There are many species of birds that are only found in this area and a major oil leak may have catastrophic consequences to the bird life around these islands. Nightingale Island and the closeby Middle Island host breeding populations of seabirds numbered in millions. Another potential problem is rats finding their way from the sinking ship onto the island and this is a real threat to burrow nesting birds. A salvage tug, the Smit Amandla, was dispatched from Cape Town on 17 March, and is expected to arrive on 21 March. The distance from Cape Town is about 2000 km. On board the tug is Estelle van der Merwe, who was in charge of SANCCOB at the time of the Treasure oil spill, and she is working in close collaboration with SANCCOB.
'More news, especially as it relates to oiled birds, will follow here as it becomes available.'
Well, a news blackout was pretty rapidly imposed. And very little information emerged at the time. But now at last, the final report from the shipping investigation has been released. This maritime safety document deals with what can only be described as the head-on collision between the bulk carrier Oliva and Nightingale Island. The wreck produced a massive oil spill in the Tristan da Cunha group. The 51-page document can be downloaded here. Here are some of the summarizing points in the report.
• Oliva ran aground because the planned course the vessel was following on the plotting sheet was found to have taken the vessel directly over Nightingale Island.
• Although the bridge team was aware that the vessel would be passing close to some islands, it was not aware as to when that event would take place.
• Although the vessel did not have BA chart 1769, other appropriate available charts covering the area had not been used.
• Both the second mate and chief mate were not aware that the vessel was heading towards Nightingale Island. This was because there was no indication on the plotting chart to alert them of the dangers ahead.
• Both the second mate and chief mate saw some echoes on the radar screen, but did not investigate them and dismissed them as rain clouds.
• There was no suitable mark placed across the ship's track to indicate the need to change to a hydrographic chart.
• Neither officer had consulted BA chart 4022. Although this chart was of an unsatisfactory scale, it could have prompted them to adopt a precautionary approach when radar echoes were sighted on the radar.
• The combination of the cold, the medication, lack of sleep, the time of the day and reaction to the vessel's grounding suggests that the chief mate was probably not fit to stand a navigational watch.
• Although the company had provided comprehensive guidance and procedures in its SMS to prevent this accident, these were not followed on board.
• The passage plan did not comply with the company's instructions of clearing distances when a vessel was in open waters.
• The master made no reference to the passing of Islands in his night orders. Reference to the Islands, could have alerted the second mate and chief mate to the significance of radar echoes.
• The handing over checklist required the chief mate to establish the proximity of any hazards to the vessel. This appears not to have happened and he relied on the brief hand-over he received from the second mate.
• The chief officer did not check the position which the able-bodied seaman plotted on the chart.
Gosh, what a disgrace – this is a disaster which was ridiculously preventable.