The firm slashed its price target on the animals for entertainment company to $15 from $22. When SeaWorld went public in 2013 its IPO price was $27.
"Hope of a turnaround have faded again," Macquarie said in a note to investors. The company's "new rides and the new orca show appear to be falling flat."
Macquarie also sees growing competition for SeaWorld in the Orlando area as Disney DIS and Universal CMCSA continue to add new attractions into the 2020s.
"Unless SEAS demonstrates better returns from new attractions, we think the turnaround will keep getting pushed out," the firm said.
SeaWorld has been facing a decline in attendance and shifting public sentiment regarding marine mammal captivity since 2013. The documentary "Blackfish," which was released that year, brought to light the harsh realities of keeping marine mammals in a captive environment.
SeaWorld recently announced the death of a three month old baby orca at one of its parks. The baby was meant to be the last captive born killer whale at a SeaWorld park. The baby is believed to have died of pneumonia.
Marine mammal experts say a shortened lifespan is just one of the negative aspects of orca captivity. It is also said to cause hyper aggression on the part of the animals, four people have been killed by captive orcas.
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