Darwin Bird Guide Recommendations?

Hi Folks

I expect to be in Darwin early to mid May this year. With my family, none of whom bird, but I can very likely negotiate a day or so to devote to birding and wonder if anyone can recommend a Darwin guide who does one-day individual tours. That would be appreciated. And herewith a longer shot: does anyone know of a specialist botany guide? My partner does not bird, but she delights in plants; especially but not only forests. But we live in the south east, so she has very little experience of the top-end monsoonal plant life.

Thanks

Kim