Sydney イルカ had 事前の fishing 傷害
Before 存在 追求するd by sharks and dying on a popular family beach in Sydney, an adult イルカ appears to have been 本気で 負傷させるd by fishing gear, zoologists say.
The adult ありふれた bottlenose イルカ died on Saturday on Manly's Shelly Beach after 存在 spotted with noticeable 傷害s and sharks nearby.
予選 検視 results show it had a 減ずるd 団体／死体 条件, a high parasite 重荷（を負わせる） and 証拠 of a 厳しい and 現在進行中の 感染 of the tail.
While the ultimate 原因（となる） of death won't be known for a few weeks, not-for-利益（をあげる） 野性生物 organisation Taronga said the lesions on the イルカ's tail 示唆するd a previous traumatic 傷害 to the tail.
The 負傷させる likely occurred within the past year but not in 最近の weeks.
"Based upon the 外見 of the lesions, the 傷害 ... is 一貫した with an entanglement in fishing gear," 野性生物 health 事業／計画（する） officer Jane Hall said.
"All of these findings 示す that this イルカ was likely immunosuppressed and that these health 問題／発行するs had been 現在の for some time.
"This would have predisposed it to the more 最近の shark 遭遇（する）, which would be considered a normal 生態学の 過程."
The sharks に引き続いて the 2.8-metre イルカ 軍隊d the 延期 of a surf lifesaving contest and the 終結 of several beaches.
But their 多重の attacks on the 哺乳動物 were "比較して superficial", Ms Hall said.
"にもかかわらず looking serious, (they) would not have 原因（となる）d the death of this individual alone," she said.
"A healthy イルカ is very 強健な, and the sharks were 実行するing a natural 役割 in the ecosystem by predating on a sick and 負傷させるd animal and their 利益／興味 in the 負傷させるd animal just happened to take place in a very public space."
The 出来事/事件 and the likely 事前の fishing gear entanglement should serve as a 思い出の品 of humans' 衝撃 on 野性生物, Ms Hall said.
A 熟考する／考慮する published in academic 定期刊行物 Science in October 概算の nearly two per cent of all fishing gear is lost to the ocean 毎年.
That 含むd enough longline mainline to 包む the Earth 18 times and one マリファナ or 罠（にかける） for every Australian adult and child.
The イルカ's 検視 was 行為／行うd at Taronga's Australian Registry of 野性生物 Health, which operates in 新規加入 to the organisation's two 野性生物 hospitals which rehabilitate more than 1500 wild animals each year.
