Magna, page-54

I think the term commonly used is 'tree shaking'.
I've experienced this before, probably like many of us, in the same circumstances with other small O&G plays, usually in the fracc stage of proceedings when tensions are building.
There'll be a shorting or sell recommendation in the media some where, supported by unfounded rumours, that day traders act on to induce down momentum, hoping to trigger stops and a bit of panic selling - using psychology as mentioned by Will78 above.
I've seen work before, it makes some quick easy money.