Geoscience Reference
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ied by a river flood, new nesting grounds would have been stacked on top of previ-
ous ones.
Although we do not have sauropods or ornithopods today that we can study
for the effects of their nesting on local landscapes, we do have birds, or theropods,
making vast nesting grounds. As mentioned in a previous chapter, many shorebirds
makesimplescrapenests,buttheymayalsoconcentratethesenestsinvastbreeding
colonies, congregating by the thousands along oceanic and lake shorelines or on
small islands. In some instances, birds in breeding colonies, such as Australasian
gannets (
Morus serrator
), make more prominent nests as raised platforms with a
central bowl-like depression for holding eggs. They then place these nest struc-
tures close together—just slightly more than the body length of the gannet next
door—which creates regularly bumpy and dimpled surfaces with hundreds or thou-
sands of regularly spaced nests throughout their nesting grounds. While on a trip to
NewZealand,Irememberseeingandmarvelingatthegannetnestsitesthere,which
were on a few isolated marine platforms just offshore. But while gazing at these
busycoloniesandtheirnestingtraces,IalsowonderedwhetherMesozoictheropods
might have had similar structures, and over extensive areas.
Now, one would think researchers looking for examples of ground-nesting
birds that modify their environments via nesting, and as analogs to Mesozoic dino-
saurs, might be tempted to look first at ratites. But this would be a mistake, as os-
triches, emus, cassowaries, and rheas do not form breeding colonies but instead act
more like rugged individualists, albeit family-oriented ones. Rather, one of the best
examples of breeding grounds in which nesting birds remade their environments,
even affecting the locations of deltas and river channels, comes from those long-
legged pink birds we revere as lawn-ornament idols, flamingos.
Inanarticle published in2012,Jenni Scott, Robin Renaut, andBernhart Owen
described the terrain-altering effects of flamingo nesting grounds along lakeshores
in the Kenya Rift Valley of eastern Africa. Flamingos there consist of two species,
thelesserflamingo(
Phoeniconaias minor
)andthegreaterflamingo(
Phoenicopter-
