Dictation with test 1 section 4

 Good after noon everyone,  well with some of you about to go our feild work is timely, but in this afternoon seesion, I will be sharing some ideas about the reasons why groups of whales and dolphines sometime swim ashore from the sea.   Right on to the beach and most often dye in what a known is mass strandings.  Unfortunatally, this type of event is frequently currencins some of the locations you will be travelling to where sometime, tide goes out suddenly. However, there are many other theories about the causing a mass strandings. The first is the behaviour is linked to paracites. It is often found stranded animals  were infestived a large numbers of paracites. For instance, a type of warm is commonly found  in the ears of dead whale. Since marine animals rely heavily on their hearing to navigate. This type of infestation has potential to be very harmful. Another theory is related to toxics or poision.  These also have been found to contribute the death of many marine animals. Many toxins as I'm sure you aware. Originated from plants or animals.  The whale ingest these toxins in its normal feedig  behaviour the whether these poision is directly or indirectly lead to stranding a death seems to depend upon toxin involved. In 1988, for example, 14 humback whales examined of stranding along the beach of cape caught or found being poision after eating tunna contain sexitoxin. The same toxin could be fatal in human. Allternatively, it has also been suggested in some animals strand accidently by following their prey ashore in the confusion of the chase. In 1995, David therstern monitored pilot whale, the beach the after following squid ashore. However, this idea does not seem to whole true for the majority of mass stranding. Because examination of animals' stomach contains  reveal that most not been feeding as they stranded. There are also some new theories which links to stranding to humans, a growing concern is that  aloud noises in the ocean coast landings. Noises such  as knows caused by militery exercises are of particular concern have been a pinpointed as the causes some strandings of the late.  One of these a mass stranding of whales in 2000 Didbaharmas conisided closely with experimence using a new submarine detection system. There were several factors may stand out different from previous stranding. This led a research to look for a new cause. For one, all the stranded animals were healthy. In addition, the animals will spread out along 38 killo meters of coast where is more common for the animals to be founded in a group when mass strandings occur.
A final theory is related to the group behaviour and suggested sea mammals cannot ditinguish between sick and healthy leaders and who will follow sick leaders even to inevitable death.
This is a particulary interesting theory since the whales is thought to be the most social. Tooth whales, other group is stranded most frequently. the theory is also supported by evidence from a dolphines stranding in 1994. Examination of dead animals reveal that  a part from leader, all the others have been healthy at the time of the death. Without one consistant theory, however, it is very hard to frastude anything about this phenomenon except assessed animals where and when we can.
Stranding network has been established around world to aid him in rescuing animals and collecting sample from those that could not be helped. I recomded John conner's marine mammals ashore as an exellence starting point if you were interested in finding out more about this networks or establishing one yourself.