Remove parentheses from multiple citations

Does anyone know how to remove the parentheses from multiple endnote citations, and join them with a semi colon? I am using the marine ecology progress series style

Right now my citation looks like: (Ehlers et al. 2008, (Hughes et al. 2004), (Hughes & Stachowicz 2009)

I want it to look like: (Ehlers et al. 2008; Hughes et al. 2004; Hughes & Stachowicz 2009)

I have seen people suggest using “output style” but I cannot find this tab in word. Please direct me 

Thanks