Hovering arrow at the top of my website

Hi there,

This is a bit of a long shot, but I was wondering if you know of a plugin that will place a hovering arrow at the top of my homepage, so visitors know they can scroll down to view more content.

Right now I have worked this arrow into the design of my banner image, but ideally I’d like it to vanish once a visitor starts scrolling.

Test site here: http://organicweek.irenevictoria.com

A plugin or a relatively easy “how-to” if possible!

Thanks so, much!