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IDProjectCategoryView StatusDate SubmittedLast Update
0008065Dwarf FortressAnimal Populationspublic2014-08-18 04:552014-09-04 05:14
Reporterelcr111 
Assigned ToFootkerchief 
PrioritynormalSeverityminorReproducibilityalways
StatusconfirmedResolutionopen 
PlatformOSOS Version
Product Version0.40.08 
Target VersionFixed in Version 
Summary0008065: Magma crabs reproduce rapidly, spawn too much, don't leave map, reduce FPS
DescriptionSince the changes to breeding, magma crab populations quickly spiral out of control. I've not played much of the latest versions, but my first 0.40.08 fort saw 23 crabs in just over two years. I made a thread about it on the forums (http://www.bay12forums.com/smf/index.php?topic=142438.0 [^]) and others are reporting the same issue with dire FPS consequences.

It just gets worse and worse since they're extremely difficult to kill, being in the bottom of the magma sea and all, and have twins or triplets most of the time. Additionally, a player who doesn't breech most of the magma sea will never find out the cause of their fort's FPS death.
Steps To Reproduce1. Start a fort
2. Wait a few years
3. Countless magma crabs
Additional InformationAs vjek pointed out in the forum thread, you can nuke them with the 'exterminate MAGMA_CRAB' dfhack command.
TagsNo tags attached.
Relationships
has duplicate 0008151resolved Footkerchief 58 magma crabs spawn in magma sea 
Attached Files
Issue History
Date ModifiedUsernameFieldChange
2014-08-18 04:55elcr111New Issue
2014-08-18 06:54FootkerchiefNote Added: 0029213
2014-08-18 06:54FootkerchiefAssigned To => Footkerchief
2014-08-18 06:54FootkerchiefStatusnew => needs feedback
2014-08-18 07:29vjekNote Added: 0029219
2014-08-18 09:09LociNote Added: 0029221
2014-08-18 09:43FootkerchiefSummaryMagma crabs multiplying at an alarming rate, potentially killing FPS => Magma crabs reproduce rapidly, don't leave map, reduce FPS
2014-08-25 06:45FootkerchiefSummaryMagma crabs reproduce rapidly, don't leave map, reduce FPS => Magma crabs reproduce rapidly, spawn too much, don't leave map, reduce FPS
2014-08-25 06:45FootkerchiefRelationship addedhas duplicate 0008151
2014-08-25 06:46FootkerchiefNote Added: 0029605
2014-08-25 06:53ZzarkLinuxNote Added: 0029607
2014-08-25 07:16LociNote Added: 0029608
2014-09-04 05:14FootkerchiefStatusneeds feedback => confirmed

Notes
(0029213)
Footkerchief   
2014-08-18 06:54   
Need a save that shows major FPS improvement from killing the magma crabs. Is this happening with any other creatures?
(0029219)
vjek   
2014-08-18 07:29   
Demonstration save can be found here: http://dffd.wimbli.com/file.php?id=9431 [^]
(0029221)
Loci   
2014-08-18 09:09   
This is related to 0007170: the magma crabs continue to multiply because they never migrate off the map.
(0029605)
Footkerchief   
2014-08-25 06:46   
martinuzz posted a save at 0008151: http://dffd.wimbli.com/file.php?id=9511 [^]
(0029607)
ZzarkLinux   
2014-08-25 06:53   
If two magma crabs are born on the map, and start reproducing, will the offspring exit the map or will they just continue to reproduce?
If so, then this might be similar to the snowball effect, similar to zombies.

Do creatures that spawn on the map ever leave?
(0029608)
Loci   
2014-08-25 07:16   
In the thread, martinuzz stated that the crabs could have spawned previously in an unrevealed section of the map. I consider that to be the most likely scenario, and should be easily confirmed in a 40.09 save by revealing the magma sea.