How to exclude Custom Post Type from Author Template?

I’m using an author template based on WordPress’s sample author template to display my authors’ bios. I have a custom post type called Shorts. The author template displays a list of my authors’ posts, which I believe (i’m not a dev – don’t know php) is the result of the following in the author.php file:

<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
        <li>
            <a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link: <?php the_title(); ?>">
            <?php the_title(); ?></a>,
            <?php the_time('d M Y'); ?> in <?php the_category('&');?>
        </li>

    <?php endwhile; else: ?>
        <p><?php _e('No posts by this author.'); ?></p>

    <?php endif; ?>

Problem is, I don’t want it to list the custom post type shorts. What do I add (and where) to leave out my custom post type (shorts)?