Transcript Ch09 presentation studentx

Invertebrates in restoration
Invertebrate habitat
-many have life cycles with stages that require different
habitats and even ecosystems and this must be taken
into account during restoration
Ex. Freshwater mussels Fig. 9.1 require suitable habitats
for adults, parasitic glochidia larvae, host fish, and
metamorphosed juveniles (Vaughan 2010)
-some are habitat specialist and some are more generalist,
for example some have glochidia that can develop on a
wide variety of fish and others only one species
-obligate mutualists often have high host specificity Ex.
Reef forming corals must partner with specific
dinoflagellates and fig wasps can only partner with
appropriate fig species
-in some, genders require specific habitats Ex. Hine’s
emerald dragonfly Fig. 9.2 or habitat resources Ex.
Ground beetles that require decomposing wood Fig. 9.3
Figure 9.1 Freshwater mussels (Unionidae) have a complex life cycle, each stage of which has
distinct habitat requirements
Figure 9.2 This female Hine’s emerald dragonfly has returned to a wetland to breed with males
specific to wetlands after spending most of her adult life in meadows and forest clearings
Figure 9.3 A ground beetle (Nebria brevicolis) feeding on decomposing wood in an English forest
Selecting Focal (Flagship) Invertebrates
-select species rich groups that significantly overlap other
groups in resource requirements Ex. Ground beetles are
species rich and include species that feed at several
trophic levels like the detrivore on decomposing wood,
herbivores, and predators
-rare species or those threatened are often specialists with
narrow geographic ranges and restoration may be part of
their recovery plan Ex. Table 9.1
-some exist as community modules-set of obligate
mutualists that must exist together for each to survive
Ex. In UK, large blue butterfly lays eggs only on thyme and
larvae drop to ground and secrete sugar solutions that
attract a species of brood rearing ants that take them
into their burrow where they feed on ant larvae and
pupate into adult Fig. 9.4
Table 9.1
Figure 9.4 The endangered large blue butterfly exists as part of a community module, which
includes host plants from one genus, Thymus (thyme), and one species of brood-rearing ants
Habitat Restoration-Habitat Structure
Figure 9.5 A single rock in a river channel provides microhabitats that support a wide range of
aquatic invertebrate species and functional groups
Figure 9.6 The functional group composition of ants changed over time in a restored uranium mine
in Northern Australia. Meat ants (green) did well in early succession but as plants changed typical
forest ants became as or more dominant
Habitat Restoration- Habitat Heterogeneity
Habitat heterogeneity-greater array of different types of
habitat; > supports > diversity organisms
Ex. In Iowa, the highway department manages some
roadsides for native prairie plants that provides
invertebrate habitat Fig. 9.7
Ex. In the Jarrah (eucalyptus) Forest restoration in
Western Australia, ant fauna is more diverse when a
more diverse seed mix was used and was more similar
to nearby reference sites Fig. 9.8
Ex. River restoration teams add heterogeneity by adding
coarse woody debris and creating structures that cause
high and low-flow environments Fig. 9.9
Figure 9.7 Butterfly diversity is twice as high on restored prairie roadsides like this one as on
roadsides planted with only one or a few introduced species
Figure 9.8 The similarity of ant species composition in planted, seeded, and naturally recolonizing
restored jarrah forests to that of reference sites
Figure 9.9 Physical habitat heterogeneity can be restored to rivers by adding coarse woody debris,
creating bank structures, and installing features to create riffles and pools
Habitat Restoration- Landscape-scale stressors
-habitat fragmentation, pollution, and altered species
interactions are some of landscape-scale stressors
involved in invertebrate restoration
-habitat fragmentation follows tenants of island
biogeography theory in regard to immigration-islands
(restoration sites) closer to mainland (colonization
source) have more diversity Fig. 9.10
-pollution like sewage is particularly important in aquatic
ecosystems causing eutrophication Fig. 9.11
-increases of the coral-predator crown-of-thorns seastar,
which may be related to overfishing (removes juvenile
seastar predators) cause changes in species interactions
and has affected the Great Barrier Reef ecosystem
-no-take fishing zones have fewer outbreaks Fig. 9.12
Figure 9.10 In rainforests of Queensland, Australia, older restoration sites and those closer to
rainforests had a more rainforest-like beetle composition
Figure 9.11 Sewage outfall in a coral reef contributes to eutrophication
Figure 9.12 (A) Crown-of-thorns starfish preying on corals. (B) Crown-of-thorns starfish outbreaks
on the Great Barrier Reef, 1992–2004, for mid-shelf reefs where most outbreaks occur
Nontarget impacts of restoration actions on invertebrates
Figure 9.13 (A) The cottony cushion scale, which feeds on plant sap, was introduced to the
Galápagos Islands from Australia and affected several rare plant species. (B) Scale populations
were reduced by introducing a ladybird beetle that only feeds on the scale.
Invertebrate species translocations
-9% of reintroduction programs worldwide involve
reintroductions even though invertebrates constitute 77%
of species on the planet
-since many endangered invertebrates are habitat
specialist precise information about the species life cycle
and its connections to habitat are crucial
-be sure source populations are large enough to survive
losing individuals for translocation Ex. New Zealand’s
Mana Island restoration involved removal of introduced
mice which allowed population of wetas to dramatically
increase and be used for reintroduction to other islands
Fig. 9.14
-Rescues of invertebrates when habitat has been
destroyed can also be used in translocations Ex. Coral
obtained after ship groundings and re-attached or used
to establish coral nurseries Figs. 9.15-9.16
Figure 9.14 Cook Strait weta populations on Mana Island were used as source populations for
translocations to nearby islands
Figure 9.15 Diver reattaching small colonies of coral to a stable reef substrate using epoxy
Figure 9.16 This coral nursery raises corals for reef restorations in the Red Sea, Israel
Captive breeding and releases
-must determine methods of capture and transport,
numbers needed for genetic diversity, food sources,
housing, sanitation, control of environmental conditions,
and colony maintenance
-removing many individuals from wild populations can
increase the risk of that population becoming extinct and
one way to reduce impact to source populations is to
collect eggs and larvae from species with long-lived
adults like mussels where glochidia from gills are used
for captive breeding Fig. 9.17
-founder populations from near the restoration should be
used so the source population and release site are well
matched in terms of environmental conditions Ex. Large
blue butterfly reintroductions into the United Kingdom
had to take into account the migration patterns to allow
adults to lay eggs on thyme flower buds Fig. 9.18
Figure 9.17 A mussel recovery specialist for the Aquatic Wildlife Conservation Center checks units
for rearing juvenile mussels at the AWCC’s facility in Marion, Virginia
Figure 9.18 A large blue butterfly larva on Thymus flower buds. Restoration sites had to have
flowers in bud at the same time as source sites for success
Releases-Hard or Soft?
Figure 9.19 Restorationists releasing larvae of the marsh fritillary (Euphydryas aurinia) near the
River Liza in the U.K.
Figure 9.20 The regal fritillary (Speyeria idalia) was reintroduced to the Neal Smith National Wildlife
Refuge using a “soft release” approach. The cage was left out for a month and contained nectar
bearing violets that allowed the gravid butterflies to acclimate before being released.
Management of invertebrate habitat
Management of invertebrate habitat
Figure 9.21 The blue-winged grasshopper lays its eggs in open habitats on coastal dunes, but
requires dense patches of vegetation for feeding
Monitoring invertebrates in restored ecosystems
Three common approaches and examples:
Figure 9.22 Scientists used network analysis to understand why a typical bumblebee parasitoid of
ancient heathlands was much less prevalent in restored heathlands in the U.K. After 15 years, the
networks were still different.