Rhiannon Meier (National Oceanography Centre, Southampton, UK,) and colleagues have published in the open-access journal Diversity and Distributions on the foraging behaviour of the Critically Endangered and ACAP-listed Balearic Shearwater Puffinus mauretanicus.

The paper’s abstract follows:

“Aim.  The movement patterns of marine top predators are likely to reflect responses to prey distributions, which themselves can be influenced by factors such as climate and fisheries.  The critically endangered Balearic shearwater Puffinus mauretanicus has shown a recent northwards shift in non-breeding distribution, tentatively linked to changing forage fish distribution and/or fisheries activity.  Here, we provide the first information on the foraging ecology of this species during the non-breeding period.

Location.  Breeding grounds in Mallorca, Spain, and non-breeding areas in the north-east Atlantic and western Mediterranean.

Methods.  Birdborne geolocation was used to identify non-breeding grounds.  Information on feather moult (from digital images) and stable isotopes (of both primary wing feathers and potential prey items) was combined to infer foraging behaviour during the non-breeding season.

Results.  Almost all breeding shearwaters (n = 32) migrated to non-breeding areas in the Atlantic from southern Iberia to the French Atlantic coast, where the majority of primary feather moult took place.  Birds foraging off western Iberia yielded feather isotope ratios consistent with a diet composed largely of pelagic fishes, while the isotopic composition of birds foraging in the Bay of Biscay suggested an additional contribution of benthic prey, most likely from demersal fishery discards.

Main conclusions.  Combined application of geolocators and stable isotopes indicates spatial variation in dietary behaviour and interactions with fisheries.  Our results imply that both pelagic fish and fisheries discards are important components of diet during the non-breeding period, which may have implications for the at-sea distribution of this migratory species.  These findings will contribute to bycatch mitigation in non-breeding areas and provide baseline data that should inform future assessment of seabird responses to changing fishery practices and prey distributions.”

Balearic Shearwater at sea

With thanks to Miguel McMinn for information.

Reference:

Meier, R.E., Votier, S.C., Wynn, R.B., Guilford, T, McMinn Grivé, M., Rodríguez, A., Newton, J., Maurice, L., Chouvelon, T., Dessier, SA. & Trueman, C.N. 2016.  Tracking, feather moult and stable isotopes reveal foraging behaviour of a critically endangered seabird during the non-breeding season.  Diversity and Distributions 1-16.  DOI: 10.1111/ddi.12509.

John Cooper, ACAP Information Officer, 29 November 2016

Lyndon Perriman, Department of Conservation Head Ranger at New Zealand’s Taiaroa Head, has made another interesting report on goings on in the mainland Northern Royal Albatross Diomedea sanfordi colony, this time on the fate of a bird whose body was previously spotted below the colony.  His Facebook report, with minor editing, follows.

Yesterday we received the body of the dead albatross [see here] from the bottom of the cliff.  She was banded GOR, a 36-year old.  Her wing bone had snapped apart indicating a severe hit from the cliff or impact with the rocks below.

GOR and her partner had fledged eight chicks from their 11 breeding attempts (spread over an 18-year period as they are a biennial breeding species).  Four of those chicks are old enough to have spent enough time at sea to return at around four or five years and all four are breeding this season. The three other chicks are yet to return.

This pair last bred in the 2014/15 season.  However, her mate failed to return from sea at around March 2015 when their chick was still young and small.  We had no foster nests to foster that chick to other parents so we ended up playing what we term "musical chick" moving chicks between their nest (where GOR was present) and two other nests (containing the two oldest chicks).  At the same time we supplementary-fed GOR, so that with food in her stomach she would stay at the nest.

We needed to do this as GOR had no food left to feed her chick and if she left the nest to go to sea to feed, her young chick would not survive the night alone.

Each day we would move chick 1 to nest 2, move chick 2 to nest 3 and move chick 3 to nest 1 (and move them to the next nest in the following day, leaving one of the older chicks always at GOR's nest overnight so that if GOR did leave, the older chick probably would survive alone overnight).  We can only do this chick rotation during the first one to two months when parents will readily accept any young chick we place in their nest (they will not go to other nests and feed other chicks, but are fixated on their own nest and therefore look after whoever is in their nest.  After a few months they can recognise their own chick and won't feed nearby chicks).

Our supplementary food is pretty good, but not as good as food from the adult, so by exchanging chicks between three nests it meant that the poorer-quality food we gave GOR wouldn't just be fed to her chick alone, thus avoiding potential problems of that chick caused  by a nutrient deficiency.

With three chicks that look very much alike, and a semi-complicated process of moving chicks once or twice a day it was a bit of a headache for staff arriving each day and working out which nest had which chick and where it had to go to for the day or for part of the day.
But the good news was that after a couple of weeks GOR's chick was large enough to survive time alone and GOR naturally entered the post-guard stage (where in a normal situation both parents leave the nest to go to sea to find food for the chick, returning to feed the chick over the next six to seven months until it fledges).

With GOR now in the post-guard stage, and the other two chicks returned to their parents, it would take both parents to raise one chick.  So over the next seven months we supplementary-fed the chick when GOR was out at sea finding food for her chick.  Feeding four times a week, it was a very long seven months, but it did mean that both the chick and GOR survived.

Like all other Northern Royal Albatrosses after fledging a chick the adults take the next 12 months off (the 2015/16 season for GOR was spent out at sea) before returning to attempt to breed again. However, if she had not accidentally hit the cliff, it would have been another three or so years before GOR would have found another mate, formed a strong pair bond and started to breed once more.

Northern Royal Albatross family at Taiaroa Head, photograph by Junichi Sugishita

View a video clip and read more on the current breeding season here.

John Cooper, ACAP Information Officer, 28 November 2016

Gohar Petrossian (Department of Criminal Justice, City University of New York) and colleagues have published in the journal Oryx on the relationship between illegal longline fishing and the threatened status of the World’s albatrosses.  The paper's abstract follows.

“Birds are commonly entangled in long-line fisheries, and increases in long-line fishing activity have consistently caused declines in seabird populations.  Environmental criminology would posit that the risk of such declines is greater in the case of illegal long-line fisheries, which are less likely to implement bycatch mitigation measures.  To investigate this possibility we examined the overlap between data on illegal fishing and albatross at-sea occurrence ranges.  Moderate correlations were found between mean exposure to illegal fishing and the Red List status of albatross species, but none were found between Red List status and total fishing pressure.  A second analysis overlaid albatross at-sea occurrence ranges with long-lining data for the member countries of the Convention on Conservation of Southern Bluefin Tuna to compare the effect of exposure to legal and illegal hooks on Red List status.  Lacking a better measure, Country A's hooks were used as a proxy for illegal hooks.  Critically Endangered and Endangered species were 12 and 3.4 times more exposed to illegal hooks, respectively, than Near Threatened species, whereas there was no relationship between Red List status and exposure to legal hooks.  Country-level analyses confirmed these findings, which provide evidence that illegal long-line fishing poses a particular threat to the survival of albatrosses.  The findings suggest that the bird conservation lobby should work closely with fisheries authorities to tackle illegal fishing, and that research should identify the highest risk areas of overlap between illegal fishing and albatross at-sea ranges.”

Critically Endangered Amsterdam Albatross at sea, photograph by Kirk Zufelt 

Reference:

Petrossian, G.A., de By, R.A. & Clarke, R.V. 2016.  Illegal long-line fishing and albatross extinction risk.  Oryx doi.org/10.1017/S0030605316000818.

John Cooper, ACAP Information Officer, 25 November 2016

Lyndon Perriman is the New Zealand Department of Conservation Head Ranger for the mainland breeding colony of Endangered Northern Royal Albatrosses Diomedea sanfordi at South Island’s Taiaroa Head.  His latest report on the 2016/17 season now underway shows the careful hands-on management this mainland colony receives.

Lyndon Perriman (left) and Junichi Sugishita get hands on with a Northern Royal Albatross at Taiaroa Head, photograph by Keith Payne

“35 nests and I think that is all we can expect for the 2016/17 season (we generally get around the mid 30's each year, a number that is growing, albeit slowly).  This includes two female-female pairs, each have laid one egg giving us a total of 37 eggs laid.

Today I candled many of the eggs with a torch and could see that almost all the eggs I looked at today were fertile, including our webcam pair (BK/RBK nest)  The only infertile eggs that I've found (from the 30 candled today) were three of the four laid by the two female-female pairs.

These extra eggs were in the incubator until they were old enough to determine fertility and one of these in the incubator was fertile so it has been placed back under one of its mums at the nest (as she was still present incubating their other egg).  Their other egg was infertile so it was removed before the fertile egg was placed back at the nest.

Both eggs from the other female-female pair were infertile so they too have been removed from the incubator.  They failed to make an actual proper nest this season, so that pair can't be used as foster parents this season, but they have raised foster chicks in previous seasons.  I think the problem this year was choosing a nest site very close to another pair and while these two females were out at sea the male of the next pair has taken guard of the area, not allowing the female-female pair actually to get back to their site.  One laid the egg on a sloping hill, the other nearby in a poorly formed nest that she started making the day before she laid her egg.

On a sadder note, we have seen an albatross dead at the bottom of the cliff, presumably an accidental clipping of the cliff or sudden loss of wind as it was coming in or leaving the headland in recent days.  It is in an area that requires boat access and that won't occur for some time as it is also in a fur seal breeding colony, making recovery of the body more problematic (fur seals become very territorial of their breeding grounds over November and December and charge people rather than flee when in full breeding mode).

We have spied a green band on its leg, so we have narrowed it down to one of 14 birds seen this season with a green band, that we haven't seen over the last few days (seven breeding birds and seven adolescent birds), so if you see any bird with a green band via the webcam, take a screen shot of it (if the webcam plays nicely) and let us know, thanks.

While it is a loss, it is a natural event and populations can withstand these events.  It’s all the other non-natural things like introduced predators and pests that cause major issues for this and other species.

Today we saw bird number 100 and 101 for the 2016/17 season.  The remaining eggs will be candled next week.”

Watch a recent video clip featuring Lyndon Perriman discussing the current breeding season and read more in ACAP Latest News about Taiaroa Head’s albatrosses here.

John Cooper, ACAP Information Officer, 24 November 2016