More than 700 seals have been recorded in the Thames Estuary.
In the first ever count by air, land and sea, the Zoological Society of London found hundreds of grey and harbour seals along the Thames and in small creeks and rivers.
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It is the fourth time in five years that the London borough has topped the rankings, according to data from the ONS.
Catherine Burke's body was discovered at a house in a quiet street in Muswell Hill last Thursday evening.
Residents said living next to the 40 foot high stinking mound was a 'living nightmare'.