4.2.8 Climate Change
Climate change is a very broad, long-term, and complex process that affects global
ecologies in a chain reaction across organismal relationships. Due to its long
temporal nature, climate change in relation to the highly seasonal life cycle of bees
can be challenging to study. The most symptomatic effect of climate change in the
pollinator-plant relationship is the influence upon plant flowering time, which in turn
can affect the pollinators’ primary food sources.
An early observation of potential climate change effects upon pollinator activities, particularly the honey bee, came from a NASA oceanographer, Wayne Esaias,
who observed changes in his hobbyist beehives; his background and access to large
data sets allowed him to piece together the effects of climate change upon local flora
and thus his honey bees. Esaias began noticing changes in his hives in the early
2000s, where the hive weight in preparation for overwintering showed symptoms
that local Maryland flowering was occurring earlier in the year, an observation
in-line with long-term trends from flowering records dating back to the 1970s.
The co-dependency of pollinators and plants can be interrupted by climate
changes when their respective life cycles in response to the environment shift in
different ways. The relationship between plants and their pollinators are at risk for
desynchronizing when environmental cues are different and when there is not
sufficient overlap of generalist pollinator populations. For example, some insects’
larval stage is timed to mature when local flowers first bloom and nectar begins to
flow. The pollinator for one plant may begin foraging when air temperature rises to a
specific point, but that plant may begin to produce flowers and nectar flow when the
snow melts [74].
While some of the earliest observations of climate change effects upon pollinators
came from managed honey bees due to necessary human interaction and thus
accessibility of data, wild pollinators have not been entirely ignored. However,
because the habitats and life cycles of typically nonsocial wild species can vary
substantially as opposed to the standardized rearing of the European honey bee,
research on wild bees must be taken with understanding of native wild plants and the
local ecology instead of standardized agricultural crops.
A Colorado, US study indicated that local environmental conditions are the
primary cues for insect emergence, particularly between wild plants that have
evolved alongside a number of wild pollinators. Furthermore, seasonal cycles of
plants, bees, and wasps in the area are regulated similarly by temperature, but plants
are more likely than insects to advance their cycle in response to spring warming.
Thus, flowering before the emergence of local pollinators is a real possibility
according to the 2011 Colorado study. Despite that risk, none of the native pollinators were specialized to a single plant species, which helps mitigate more catastrophic cycle shifts in specific plant species if the pollinator were completely
dependent. However, even generalist bees may be affected as both larval development and survival can vary by available pollen diet.
1 Understanding, Conservation, and Protection of Precious Natural Resources: Bees
27
Climate change is a very broad, long-term, and complex process that affects global
ecologies in a chain reaction across organismal relationships. Due to its long
temporal nature, climate change in relation to the highly seasonal life cycle of bees
can be challenging to study. The most symptomatic effect of climate change in the
pollinator-plant relationship is the influence upon plant flowering time, which in turn
can affect the pollinators’ primary food sources.
An early observation of potential climate change effects upon pollinator activities, particularly the honey bee, came from a NASA oceanographer, Wayne Esaias,
who observed changes in his hobbyist beehives; his background and access to large
data sets allowed him to piece together the effects of climate change upon local flora
and thus his honey bees. Esaias began noticing changes in his hives in the early
2000s, where the hive weight in preparation for overwintering showed symptoms
that local Maryland flowering was occurring earlier in the year, an observation
in-line with long-term trends from flowering records dating back to the 1970s.
The co-dependency of pollinators and plants can be interrupted by climate
changes when their respective life cycles in response to the environment shift in
different ways. The relationship between plants and their pollinators are at risk for
desynchronizing when environmental cues are different and when there is not
sufficient overlap of generalist pollinator populations. For example, some insects’
larval stage is timed to mature when local flowers first bloom and nectar begins to
flow. The pollinator for one plant may begin foraging when air temperature rises to a
specific point, but that plant may begin to produce flowers and nectar flow when the
snow melts [74].
While some of the earliest observations of climate change effects upon pollinators
came from managed honey bees due to necessary human interaction and thus
accessibility of data, wild pollinators have not been entirely ignored. However,
because the habitats and life cycles of typically nonsocial wild species can vary
substantially as opposed to the standardized rearing of the European honey bee,
research on wild bees must be taken with understanding of native wild plants and the
local ecology instead of standardized agricultural crops.
A Colorado, US study indicated that local environmental conditions are the
primary cues for insect emergence, particularly between wild plants that have
evolved alongside a number of wild pollinators. Furthermore, seasonal cycles of
plants, bees, and wasps in the area are regulated similarly by temperature, but plants
are more likely than insects to advance their cycle in response to spring warming.
Thus, flowering before the emergence of local pollinators is a real possibility
according to the 2011 Colorado study. Despite that risk, none of the native pollinators were specialized to a single plant species, which helps mitigate more catastrophic cycle shifts in specific plant species if the pollinator were completely
dependent. However, even generalist bees may be affected as both larval development and survival can vary by available pollen diet.
1 Understanding, Conservation, and Protection of Precious Natural Resources: Bees
27