Die witkruisarend word dikwels verkeerdelik daarvan beskuldig dat hy lammers doodmaak, volgens die Predasiebestuursforum van die Noord-Kaap.
Die arend is baie voordelig vir die meeste boere omdat dassies sy hoofbron van voeding is. ‘n Broeipaar arende met hul kuikens vreet ongeveer 350 dassies per jaar, wat help om die getalle te beheer. Dié hoeveelheid dassies vreet nagenoeg dieselfde hoeveelheid veld as wat 22 gesonde skape in ‘n jaar sou eet. Die meeste arende is opportunistiese voeders en sal by tye groot hoeveelhede kleiner ongediertes wat in groot volumes voorkom soos termiete, knaagdiere en sprinkane vreet. Dus voorsien die roofvoël gratis plaagbeheer. Witkruisarende beskik nie oor die fisieke krag om ‘n skaap- of boklammetjie van ouer as drie weke te vang nie. Indien daar genoegsame kleiner wild soos dassies op die plaas is wat hulle as ‘n bron van voedsel kan gebruik, sal hulle nie sommer ‘n lammertjie vang nie. Hulle aas soms op die lammetjies wat doodgebore is of wat reeds deur ander predatore doodgemaak is.
Tekens dat ‘n arend ‘n lam gevreet het, maar nie noodwendig doodgemaak het nie:
· Uitpluk van groot bondels pels of wol.
· Die vleis tussen beentjies sal uitgepik wees, dus sal die karkas skoongevreet wees. Slegs die punte van ribbes word soms afgebreek.
· Die lam sal kloumerke teen die kop hê of in meer gevalle sal die nek of bo-rugbene vergruis wees weens druk van sy kloue.
· Onreëlmatige gespasieerde gaatjies in die vel en moontlik op die kopbeen.
· Onder die vel rondom hierdie gaatjies sal daar geweldige kneusing en bloeding wees wat deur die kragtige greep veroorsaak is.
· Lang senings sal nog aan die bene wees.
Hoe om te identifiseer of ‘n lam dood is voor of ná geboorte:
· As die hoewe nog membraandoppies op het, het die dier nie geloop of gespartel nie en is dus doodgebore.
· Indien die dier nog nooit asemgehaal het nie sal die longe ‘n dieprooi kleur wees.
· Die lewer sal ‘n harde gevoel hê en sal nie pienk en sponserig wees nie.
· Die afwesigheid van bloedklonte aan die einde van ‘n naelstring.
· ‘n Lam wat swaargekry het tydens geboorte is goudgeel gevlek met mekonium en heel moontlik dood tydens geboorte of kort ná die geboorteproses.
· ‘n Siek of verhongerde lam se vet is rooibruin en jellierig.
· Afwesigheid van melk of kos in melkpensie.
Dit is uiters belangrik om die regte roofdier te identifiseer wanneer lammers doodgemaak word. ‘n Verkeerde identifikasie kan lei tot verdere en groter skade omdat die regte predasiebeheermetodes nie toegepas word om die werklike sondebok te vang nie. Alle diere speel ‘n belangrike rol in die ekologie en voor- en nadele moet altyd opgeweeg word. Die omgewing moet ook in ag geneem word om te bepaal hoe die ekologie versteur is, wat dalk gelei het tot ‘n afname in kleinwild, die primêre bron van voedsel vir die meeste roofdiere.
Foto bron: http://www.waterberg-bioquest.co.za/Bird%20spp%20pgs/131VeEgl.html
The white-crested eagle is often wrongly accused of killing lambs, according to the Northern Cape Predation Management Forum.
The eagle is very beneficial to most farmers because badgers are its main source of nutrition. A breeding pair of eagles with their chicks eat around 350 badgers a year, which helps to control the numbers. This number of badgers eat almost the same amount of field as 22 healthy sheep would eat in a year. Most eagles are opportunistic feeders and will at times eat large quantities of smaller animals that occur in large volumes such as termites, rodents and grasshoppers. So, the raptor provides free pest control. White-crested eagles do not have the physical strength to catch lambs older than three weeks. If there is sufficient smaller game such as badgers on the farm which can be used as a source of food, they are not likely to catch a lamb. They sometimes prey on lambs that are stillborn or lambs that have already been killed by other predators.
Signs that an eagle has eaten a lamb, but not necessarily killed it:
- Large bundles of fur or wool will be plucked out.
- The meat between the bones will be picked out, so the carcass will be eaten clean. Only the ends of ribs are sometimes broken off.
- The lamb will have claw marks on the head or in more cases the neck or upper back bones will be crushed due to pressure from the eagle’s claws.
- Irregularly spaced holes in the skin and possibly on the skull.
- Under the skin around these holes, there will be tremendous bruising and bleeding caused by the forceful grip.
- Long tendons will still be on the legs.
How to identify if a lamb died before or after birth:
- If the hooves still have membrane caps on them, the animal did not walk or frolic and was therefore stillborn.
- If the animal has never breathed before, the lungs will be a deep red colour.
- The liver will feel hard and will not be pink and spongy.
- The absence of blood clots at the end of an umbilical cord.
- A lamb that suffered during birth is spotted golden yellow with meconium and most likely died during birth or shortly after the birth process.
- A sick or starving lamb’s fat is reddish brown and jelly-like.
- Absence of milk or food in milk belly.
It is extremely important to identify the correct predator when lambs are killed. A wrong identification can lead to further and greater damage because the right predation control methods will not be applied to catch the real scapegoat. All animals play an important role in the ecology, and advantages and disadvantages must always be weighed. The environment must also be taken into account in order to determine how the ecology has been disturbed, which may have led to a decrease in small game, the primary source of food for most predators.
Photo source: http://www.waterberg-bioquest.co.za/Bird%20spp%20pgs/131VeEgl.html