HOME >> BIOLOGY >> NEWS
Coastal Birds "Feel" Their Prey Under The Sand

Knots (a kind of sandpiper) can locate their favourite food -shellfish- under wet sand by inserting their beak half a centimetre into the sand for a few seconds. Scientists at the NWO's Netherlands Institute for Sea Research (NIOZ) and the universities of Groningen and Leiden have carried out experiments to demonstrate this. The birds' ability to do so seems to be based on a hydro-dynamic principle.

The locational ability of the knots was demonstrated in experiments in which the researchers hid little stones in the sand. That the birds can detect stones is remarkable because stones obviously enough do not send out any signals. They do not move, their temperature does not differ from that of the sand, and they have no smell or electro-magnetic field; they can therefore not be observed with the birds' normal sense organs. The birds' ability to detect them nevertheless must therefore be based on their beaks' being sensitive to differences in currents in the water in wet sand between the individual grains, stones, or shells. Tame knots used in the experiments were unable to find hidden stones in dry sand.

Under the horny layer of the end of their beak, knots have clusters of 10 to 20 corpuscles of Herbst in the bone and these are sensitive to differences in pressure. When the bird sticks its sensitive beak into the sand at low tide, it produces a pressure wave because of the inertia of the water in the interstices between the particles. The pattern thus created betrays the presence of objects which are larger than the grains of sand. Knots are able to read the disturbances in the pressure field and perhaps even amplify it to some extent. The rapid up-and-down movements of the bird's beak loosen the grains of sand, which then become packed together more tightly, displace the interstitial water and cause the residual pressure around the object concerned to increase.

The birds' ability to detect food also explains why knots can find enough to eat on inte
'"/>

Contact: Dr. Theunis Piersma
theunis@nioz.nl
31-222-369300
Netherlands Organization for Scientific Research
9-Feb-1999


Page: 1 2

Related biology news :

1. ESA Corporate Award winner 2001: Weyerhaeuser Company Limited British Columbia Coastal Forest Project Team
2. Coastal research project at UC Santa Cruz receives major boost in funding
3. Killer Whales Have Begun Preying On Sea Otters, Causing Disruption Of Coastal Ecosystems In Western Alaska
4. As A Carbon Sponge, Iron-Poor Coastal Waters Cant Always Do The Job, NaturePaper Shows
5. Water Quality In Georgia-Florida Coastal Plain Affected By Agricultural And Urban Activities
6. Coastal Development Threatens Rare Atlantic Shorebird
7. Birds show superior listening skills
8. Birds use herbs to protect their nests
9. Birds do it. Bugs do it. But why dont we?
10. Birds and humans have similar shopping habits
11. Chemical evidence proves the old adage, Birds of a feather flock together

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:4/5/2017)... -- Today HYPR Corp. , leading innovator in ... the HYPR platform is officially FIDO® Certified . ... that empowers biometric authentication across Fortune 500 enterprises and ... 15 million users across the financial services industry, however ... suites and physical access represent a growing portion of ...
(Date:4/4/2017)...   EyeLock LLC , a leader of iris-based ... Patent and Trademark Office (USPTO) has issued U.S. Patent ... an iris image with a face image acquired in ... 45 th issued patent. "The ... the multi-modal biometric capabilities that have recently come to ...
(Date:3/30/2017)... , March 30, 2017  On April 6-7, ... Hack the Genome hackathon at Microsoft,s headquarters ... two-day competition will focus on developing health and wellness ... Hack the Genome is the first ... tremendous. The world,s largest companies in the genomics, tech ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... 11, 2017 , ... Personal eye wash is a basic first aid supply for any work ... which eye do you rinse first if a dangerous substance enters both eyes? It’s one ... with its unique dual eye piece. , “Whether its dirt and debris, or an ...
(Date:10/11/2017)... ... October 11, 2017 , ... ... it will be hosting a Webinar titled, “Pathology is going digital. Is your ... on digital pathology adoption best practices and how Proscia improves lab economics and ...
(Date:10/11/2017)... and LAGUNA HILLS, Calif. , ... of Cancer Research, London (ICR) and ... with SKY92, SkylineDx,s prognostic tool to risk-stratify patients with multiple ... as MUK nine . The University of ... is partly funded by Myeloma UK, and ICR will perform ...
(Date:10/11/2017)... , ... October 11, 2017 , ... ... the implantation and pregnancy rates in frozen and fresh in vitro fertilization ... progesterone and maternal age to IVF success. , After comparing the results from ...
Breaking Biology Technology:
Cached News: