def get_bottom(depths, des_mask, asc_mask):
    """Get boolean mask of regions in depths the animal is at the bottom

    Args
    ----
    des_mask: ndarray
        Boolean mask of descents in the depth data
    asc_mask: ndarray
        Boolean mask of ascents in the depth data

    Returns
    -------
    BOTTOM: ndarray (n,4)
        Indices and depths for when the animal is at the bottom

        *Index positions*:

        0. start ind
        1. depth at start
        2. stop ind
        3. depth at stop
    """
    import numpy
    from . import utils
    des_start, des_stop = utils.contiguous_regions(des_mask)
    asc_start, asc_stop = utils.contiguous_regions(asc_mask)
    bottom_len = min(len(des_stop), len(asc_start))
    bottom_start = des_stop[:bottom_len]
    bottom_stop = asc_start[:bottom_len]
    BOTTOM = numpy.zeros((len(bottom_start), 4), dtype=float)
    BOTTOM[:, (0)] = bottom_start
    BOTTOM[:, (1)] = depths[bottom_start]
    BOTTOM[:, (2)] = bottom_stop
    BOTTOM[:, (3)] = depths[bottom_stop]
    return BOTTOM
