I noticed I needed to re-caulk the tub/shower in the bathroom (purchased this house 5 months ago). When i pulled the old caulk I came across a decent amount of moisture and a black pasty substance (first image). I had some concerns about mold buildup but scraped and scrubbed as much as I could out then "flushed" by pouring a cup of water down the shower wall to create a vacuum and pull out additional debris. When I did this, another substance came out that appears to be droppings of some kind (second image).
Any thoughts on what I need to do? My gut says I need to pull the wall boards off and see what's happening behind them, but with a baby due in three weeks, NOBODY wants to create a huge mess and headache.

It looks like termite frass(poop) to me. Was a termite/pest inspection done before purchase? I would save the droppings and show them to a pest control inspector(if an inspection was done, I would contact them first).

Yes - a termite check was done before the sale where no termites were found - but - there is a history of termites and treatment at the house. We have a warranty from the treatment that I will follow up on in the morning. Thanks for your input.
On a further note, I contacted the home inspector that I used prior to the sale for his thoughts and he suggested that the matter may be cricket poop and because of our dryness (Arizona), a solution may be to clean, dry and properly caulk so no additional water can get in. His thoughts were that any leftover moisture would soon dry up as long as no new water is allowed in.
I'm concerned about simply "covering it up and hoping nothing bigger is wrong"... I'd feel much better knowing there's nothing growing behind those walls that will come back to haunt us in the long run.



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my inclination is to open up the walls and start from scratch.
yeah, there is a possibility the home inspector is correct. BUT, he could be wrong as well..

Termites are kind of pest which are quite difficult to eradicate. Even after trying different household methods, there is a chance of having them back.

Yes, I agree with @JCFlax (NJ). Termites are pest which are very difficult to exterminate. I think an Integrated Pest Management approach for a safe and effective termite extermination is needed. You should consult a professional termite control expert in your local area who will help you to formulate an effective termite pest prevention strategy.
You can take some advice or tips from other pest control experts.



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