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All years Observers: 1404 Cards: 103239 Records: 5456100 Incidentals: 424931 Pentads: 12919 (74.60%)
2014 Observers: 393 Cards: 4669 Records: 249104 Incidentals: 21030 Pentads: 2263 (13.07%)
AutumnMAP Observers: 277 Cards: 1831 Records: 93625 Incidentals: 6946 Pentads: 1161 (6.70%)
Latest News
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Citizen Science Week : Saturday 8 March to Sunday 16 March

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SABAP2 at the end of the first half of February 2014

One hundred thousand checklists in the SABAP2 database: awesome milestone, well done, Team

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Five million records

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THIS COUNTDOWN CLOCK IS NOW BELOW 100

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Intergovernmental Panel on Climate Change report released

Barberspan conference 28 November – 3 December 2013

Weaver Wednesday [66]: Sao Tome Weaver

Weaver Wednesday [65]: Black-necked Weaver

Sappi TREE TUESDAY, and today we are featuring the Knobbly Creeper

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Public Lecture Wednesday 18 September "The metamorphosis of the butterfly atlas"

2000 up on Facebook

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This part of South Africa is especially important for annual coverage!

SpringMAP 2013

Weaver Wednesday: Cinnamon Weaver

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Virtual Museum records

Twenty years of CWACing the Bot River Estuary

Atlas bash to Loeriesfontein, Northern Cape, 8-11 August 2013

Save the date: 20-21 July 2013, SABAP2 workshop, Port Elizabeth

MyBirdPatch workshop: Intaka Island Enviro-Centre, Cape Town, Sat 8 June, 09:00 - 13:00

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SABAP2 workshop: Intaka Island, Century City – ths Saturday 11 May, 09h00 – 15h30

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Making the most of the SABAP2 website - 5: checking your submissions and accessing your ORFs

Making the most of the SABAP2 website - 4: finding those gaps and other interesting pentad information!

SABAP2 workshop: Intaka Island, Century City, Sat. 11 May, 9:00 am - 3:30 pm

Weaver Wednesday: Golden Palm Weaver

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Gravit8 Weaver Wednesday [44]: Speke's Weaver

Gravit8 Weaver Wednesday: Speckle-fronted Weaver

April Aliens – the Common Myna continues its march across the southern African landscape

April Aliens – if the voracious European Shore Crab reaches the Saldanha Bay-Langebaan Lagoon system, well, dot dot dot

The butterfly to think about on Threat Thursday is the Fraternal Widow

Important new paper: One-third for the birds

Les Underhill (2011-12-23)

One-third for the birds

Two of the Animal Demography Unit's Honorary Research Associates, Rob Crawford and Jean-Paul Roux, are co-authors of an important paper published in the leading journal Science today. It provides critical guidance on how fish stocks should be managed in such a way that there is enough left over for the seabirds.

"Fishing can have devastating effects on seabirds. Not only do they get snagged on hooks and tangled in nets, but chronic overfishing can deprive the birds of their prey—the same small fish that boats are catching. Now a study has identified what appears to be a universal threshold for danger: when the biomass of so-called forage fish drops below one-third of its maximum, seabirds of many species start to have fewer chicks.

"'This is one of the most important seabird papers to be published in some time,' comments conservation biologist Dee Boersma of the University of Washington, Seattle, who was not involved in the research. The findings demonstrate the widespread reliance of seabirds on small forage fish, she says. To protect the birds, the papers' authors call for lower harvest levels of forage fish. 'The problem remains that most fisheries are not properly managed and controlled,' says co-author Philippe Cury of the Institute of Research for Development in Sète, France. Worldwide, about 25% of forage fish stocks have collapsed, he adds.

These are the first two paragraphs of the report that appears on the website of the journal Science. Read the full report here.

The abstract of the paper reads like this: "Determining the form of key predator-prey relationships is critical for understanding marine ecosystem dynamics. Using a comprehensive global database, we quantified the effect of fluctuations in food abundance on seabird breeding success. We identified a threshold in prey (fish and krill, termed “forage fish”) abundance below which seabirds experience consistently reduced and more variable productivity. This response was common to all seven ecosystems and 14 bird species examined within the Atlantic, Pacific, and Southern Oceans. The threshold approximated one-third of the maximum prey biomass observed in long-term studies. This provides an indicator of the minimal forage fish biomass needed to sustain seabird productivity over the long term." The full reference is Cury PM, Boyd IL, Bonhommeau S, Anker-Nilssen T, Crawford RJM, Furness RW, Mills JA, Murphy EJ, Österblom H, Paleczny M, Piatt JF, Roux J-P, Shannon L.J, Sydeman WJ 2011. Global seabird response to forage fish depletion – one-third for the birds. Science 334: 1703–1706.


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