Reproducing Invaders

Mar Ecol Prog Ser Vol. 336: 211–223, (2007)



The green porcelain crab (Petrolisthes armatus) is an invasive species in the Southeastern United States that is present in staggering densities of several thousand individuals per square meter.  This has generated some concern among ecologists as the crabs are most common in the oyster reef habitats that form the backbone of the area’s marine ecosystem.  Research by Amanda Hollebone at the Georgia Institute of Technology has provided insight into how this non-native species is able to sustain such population densities.  

Hollebone sampled P. armatus populations throughout its new range and found that the females were reproducing at smaller sizes than in the native range.  In addition, she found that the percentage of reproducing females was similar in both ranges despite much higher population densities in the invaded regions.  These results suggest that the expanded P. armatus populations are more than capable of sustaining themselves through reproduction without the support of future immigrations.


Eli Wilber


One Response to “Reproducing Invaders”

  1.   jmb87 Says:

    Great post! But since I also did a research highlight on a crab article:
    Have existing native populations of crab helped slow down the invasion of this green porcelain crab? In my article, well established populations that contained numerous adult blue crabs (a crab native to much of the US, including, I believe, the Southeastern US) are hypothesized to be able to contain, or at least slow, the invasion of the European green crab. Have they considered breeding large populations of adult blue crab and introducing them to the green porcelain crab populations? Did they mentioned anything about whether existing native species have slowed the green porcelain crab’s progress?
    Also, since they live in such high densities, wouldn’t it be quite simple to kill large quantities of them at once? If there really are thousands per square meter, I would think that some people would take the intiative to put poison on these crabs–especially because I would think that the risk of harming other species (at least right then) would be low, since no other species would be able to live amongst the high densities of crab (perhaps?).