Terrestrial vs fossorial

[Myrlina]

I've been watching a lot of YouTube videos lately of tarantulas in the wild (birdspidersCH, lovetarantulas) and I am fascinated to see common pet species classed as terrestrial (Grammastola rosea, Lasiodora parahybana and others) spending all their time in deep burrows. Where is the line drawn between terrestrial Ts that burrow and true fossorials? I only have experience with terrestrials but I'm tempted to give them a whole lot more substrate after watching these films!

 

[Edan bandoot]

I've been watching a lot of YouTube videos lately of tarantulas in the wild (birdspidersCH, lovetarantulas) and I am fascinated to see common pet species classed as terrestrial (Grammastola rosea, Lasiodora parahybana and others) spending all their time in deep burrows. Where is the line drawn between terrestrial Ts that burrow and true fossorials? I only have experience with terrestrials but I'm tempted to give them a whole lot more substrate after watching these films!

Terrestrial is a hobby word for display tarantula pretty much.

when people say fossorial in the hobby they mean obligate burrowers as opposed to opportunistic burrowers.

All tarantulas live in some sort of hide in the wild (otherwise a bird or wasp would eat them) save for mature males

 

[viper69]

It’s all about context.

 

[Edan bandoot]

The change in husbandry that I implemented for ground dwelling species that had the biggest impact was the use of dry floral foam and yoga blocks with a burrow dug underneath it. Dry floral foam for small to medium sized species, such as Aphonopelma species, and yoga blocks for large species, such as Grammostola and Brachypelma. The blocks are buried along the longest side of a tall plastic container then with a spoon I dig out something of burrow underneath the blocks. Then using my fingers and a cardboard tube from an empty paper towel roll, I make a circular entrance to the burrow. The tarantulas then utilize the artificial burrow along the side of the container so I can see them.

This technique came to me after years of seeing the burrows of Aphonopelma hentzi in the suburbs of North Texas and noticing they almost all dug burrows along the side of a sidewalk, street curb on the grassy side, or in some cases, underneath headstones in cemeteries. The foam blocks in captivity mimic this behavior of a ground dwelling tarantula preferring to build a burrow against and underneath something sturdy and it worked great! In some cases, my tarantulas expanded the artificially crated burrow and made their own secondary entrance further exhibiting natural behavior.

The plus side is I get to see natural behavior in most of my tarantulas without spending a ton of money in materials; the downside is it is terribly ugly. Though, I would rather set up my tarantulas for natural behavior than have something pretty for me to look at but useless for the tarantula.

another interesting thing is that people don't always provide a natural hide for the spiders. I know the Grammostola genus likes to make tunnels on the underside of rocks and according to @AphonopelmaTX so do A.hentzi and Brachypelma.

practices like these (not providing adequate hides) is probably another reason why people believe in "terrestrial" tarantulas.

 

[Myrlina]

I noticed all the G.roseas in the video seemed to have dug underneath big rocks through very hard, stony soil. That's an interesting idea about using foam blocks to make an artificial tunnel.