rapp beach and creek hunting

[Rowboater]

Beautiful spring weather here!  Nothing new and exciting from me, but lots of small teeth, some colorful.  One rootless weathered cowshark tooth, bunch of glossy drum teeth, angel shark or two.  Mostly spikes, sand tiger, some with nice cusps.  The two burrows are from the beach, as is the tiger shark tooth (not much of a winter, and not many makos on the beach-- or maybe others are after them!)  Great being out, although pollen is clearly coming fast here.

 

 

 

[rand95]

Nice teeth as always.

[DawnOfADream]

Excuse my ignorance, but what are the two at the top right that look like toasted bread slices? 

[Rowboater]

@DawnOfADream Those are petrified burrows with coprolites visible, from fossil mantis/ghost like shrimp.  @Carl our resident expert believes the coprolites fall into the burrows with water flow.  Since many crustaceans burrow, I'm hoping to find visible remains of one within a burrow, but no luck so far.  Some concretions and possible arm sections, but could be from other crustaceans. Carl says he finds "shiny black" claws from these critters, but so far no luck there for me, just the coprolites.  Out resident coprolite expert @GeschWhat has been extremely helpful in identifying the coprolites (they have a nice cross-sectional pattern she has micro-photographed  from several to narrow down species) and has a lot of ideas about what they may mean.  For example, most creatures that burrow expel their fecal matter out into the tide, or may have separate chambers for them.  She wondered if they might molt in sealed off burrows?  Other (to me) similar species live in high density burrows, maybe some end up as toilets and full of coprolites?  I don't know, but was shocked at the number of scientific publications on these animals!

[Fossildude19]

Another productive hunt! 
Cool finds, as per usual.  

[DawnOfADream]

@Rowboater thanks for such a detailed answer!