diff --git a/python/lsst/pipe/tasks/calibrate.py b/python/lsst/pipe/tasks/calibrate.py
index 55ed853e6..b617eebb2 100644
--- a/python/lsst/pipe/tasks/calibrate.py
+++ b/python/lsst/pipe/tasks/calibrate.py
@@ -596,6 +596,8 @@ def run(self, exposure, background=None,
                     s.set(self.skySourceKey, True)
         if self.config.doDeblend:
             self.deblend.run(exposure=exposure, sources=sourceCat)
+        if not sourceCat.isContiguous():
+            sourceCat = sourceCat.copy(deep=True)
         self.measurement.run(
             measCat=sourceCat,
             exposure=exposure,