Here is the default footer code for that theme. Copy and paste overwriting what is in there now.
<div class="clear"></div>
<!--Start Footer-->
<div class="footer-wrapper">
<div class="container_24">
<div class="grid_24">
<div class="footer">
<?php
/* A sidebar in the footer? Yep. You can can customize
* your footer with four columns of widgets.
*/
get_sidebar('footer');
?>
</div>
</div>
</div>
</div>
<!--End Footer-->
<div class="clear"></div>
<div class="footer_bottom">
<div class="container_24">
<div class="grid_24">
<div class="footer_bottom_inner">
<span class="blog-desc">
<?php echo get_bloginfo('title'); ?>
-
<?php echo get_bloginfo('description'); ?>
</span>
<?php if (blackbird_get_option('blackbird_footertext') != '') { ?>
<span class="copyright"><?php echo blackbird_get_option('blackbird_footertext'); ?></span>
<?php } else { ?>
<span class="copyright"><a href="http://www.inkthemes.com"><?php _e('BlackBird WordPress Theme by InkThemes.com', 'black-bird'); ?></a></span>
<?php } ?>
</div>
</div>
</div>
</div>
<?php wp_footer(); ?>
</body>
</html>