The University of Southampton

Tag: bees

Honey, I can’t bee-lieve what I’m seeing!

Posted on by Luke Donovan
Why does it keep getting hotter ... and where has my home gone?!
Why does it keep getting hotter … and where has my home gone?!

Enjoying that tangerine? That glass of cranberry juice this morning? Waking up in those 100% cotton bed sheets? Well, you can thank the bees. They are the major pollinators of plants and crops in ecosystems and are invaluable to us (Brown and Paxton, 2009; Costanza et al., 1997). Unfortunately, bees are declining, mainly through human causes (boo!). Habitat loss, fragmentation, invasive species and climate change are all factors that are harming the bee populations.

Homes under the hammer – no, not the TV show

The human population is set to reach ~9 billion by 2050 (United Nations, 2004), seeing an increase in resources to feed all these mouths. Habitats need to be converted into farmland to provide crops (which ironically will be pollinated by bees!). It is known that human disturbance can negatively impact bee numbers (Winfree et al., 2009). It could also cause populations to inbreed, meaning they are susceptible to nasty diseases causing death (Brown and Paxton, 2009). The more we harm bee habitats, we are causing detriment to their numbers and are also causing a negative effect on our lives – how counterproductive.

More food and less destruction! (pintrest.com)
More food and less destruction!

How did you get here?!

Sometimes you get an unfamiliar, ugly head pop up in a population which is causing harm to the original species that live there – otherwise known as an invasive species. The process is usually:

  • Introduction
  • Colonisation
  • Naturalisation
  • Spread
  • Impact

 

This can be seen in the Africanized honeybee in South America, largely replacing the European honeybee by outcompeting it (Schweiger et al., 2009).

Left: Africanized Honey bee - Right: European Honey Bee
Left: Africanized Honey bee – Right: European Honey Bee.

Nature has no air-conditioning: Get used to the warm!

Despite belief from certain world leaders, climate change is happening. Climate change brings many problems to bee populations, such as a change in the relationship between plants and the bees and an increase in disease and parasites (Le Conte and Navajas, 2008).

In snowy environments, climate change is causing snow to melt earlier, meaning flowers are emerging earlier, causing bees to be out of sync (phenology), thus causing changes in what’s called their ‘functional traits’ which are traits that typically relate to changes in the environment.

Bees must build up sufficient honey stores so that they can survive over the winter periods, however climate change is causing a change in flower development (and pollen production) whereby drought is responsible for the decline in flower numbers (La Conte and Navajas, 2008). This means that the bees cannot build the right amount of honey stores and starve over the winter period.

The future of the bees

There are conservation efforts to try and help bees (woo!) such as (Brown and Paxton, 2009):

  • Minimising habitat loss
  • Making agricultural habitats bee-friendly
  • Training scientists and the public

 

If bees were to go extinct tomorrow, we would have to self-pollinate EVERYTHING, as bees do all this hard work for us, for nothing. If we lose bees, we lose the planet, we must ensure bees do not leave us otherwise the future will look very bleak (with no hint of yellow and black).

Thanks for reading, lets hope we see these guys buzzing around for a long time
Thanks for reading, lets hope we see these guys buzzing around for a long time.

[498 words]

References

Brown, M. and Paxton, R. (2009). The conservation of bees: a global perspective. Apidologie, 40(3), pp.410-416.

Costanza, R., d’Arge, R., de Groot, R., Farber, S., Grasso, M., Hannon, B., Limburg, K., Naeem, S., O’Neill, R., Paruelo, J., Raskin, R., Sutton, P. and van den Belt, M. (1997). The value of the world’s ecosystem services and natural capital. Nature, 387, pp.253-260.

Le Conte, Y. and Navajas, M. (2008). Climate change: impact on honey bee populations and diseases. Rev. sci. tech. Of. int. Epiz, 27(2), pp.499-510.

Schweiger, O., Biesmeijer, J., Bommarco, R., Hickler, T., Hulme, P., Klotz, S., Kühn, I., Moora, M., Nielsen, A., Ohlemüller, R., Petanidou, T., Potts, S., Pyšek, P., Stout, J., Sykes, M., Tscheulin, T., Vilà, M., Walther, G., Westphal, C., Winter, M., Zobel, M. and Settele, J. (2010). Multiple stressors on biotic interactions: how climate change and alien species interact to affect pollination. Biological Reviews, 85, pp.777-795.

United Nations (2004) World Population to 2300, New York. [online] http://www.un.org/esa/population/ publications/longrange2/WorldPop2300final.pdf

Winfree, R., Aguilar, R., Vázquez, D., LeBuhn, G. and Aizen, M. (2009). A meta-analysis of bees’ responses to anthropogenic disturbance. Ecology, 90(8), pp.2068-2076.



Nasty Neonicotinoids: The cause of declines in Birds, Bees and Butterflies

Posted on by Imogen Ryan

 

As agriculture has intensified over the last century we have seen falling food prices and bigger fruit and veg, but what is the cost to our wildlife?

The increase in size of modern arable fields provides a veritable feast for many pests, destroying large areas of crop and literally eating into farmer’s profits. This has led to a rise in the use of pesticides to control these pests. However, not all the animals that are negatively affected by pesticides are harmful to crops, in fact some are beneficial.

Neonicotinoids

In the 1990’s a group of insecticides called neonicotinoids were developed which could be added to seeds before planting rather than externally sprayed onto the plants. The plant incorporates the chemical into all its tissues, giving insect pests a fatal dose upon taking a bite (Gilburn, 2015). This is good news for those beneficial animals that don’t munch their way through the crop right?

Wrong! The chemical gets into every part of the plant including the pollen and nectar (Blacquire et al 2012) which bees and butterflies feed on while pollinating plants. Farmland birds also often eat the seeds before they sprout. These animals don’t even have to be in the field to be affected as the majority of the chemical is not taken up by the plant and is leached into the soil water (Hallman et al 2014) and transported to wildflower field margins and neighbouring land.

What are the effects? 

Butterflies

The populations of widespread butterflies on monitored UK farmland sites have declined by 58% between 2000 and 2009 (Brereton et al 2011). This is negatively correlated with the increase in the use of neonicotinoids (Gilburn, 2015). Although it has not been proved to be a cause and effect relationship, the sudden decline in butterflies has not been seen in Scotland (Brereton et al 2011) where less neonicotinoids are used (Defra, 2014).

Painted Lady Butterfly -Alamy

Bees

Neonicotinoids are also threatening bees, impairing their homing ability and learning as well as their immunity to viruses. The chemical also reduces the growth of the colony and the production of queens (Cresswell, 2011). A recent field study by Rundolf et al (2015) has shown that the density of wild bees, nesting of solitary bees and growth of bumblebee colonies have all been reduced by neonicotinoid treated rape seeds.

neonicotinoid-pesticides-their-effect-on-bee-colonies-the-facts

Out for the count. Julia Garvin

 

Birds

A decline in insectivorous farmland birds, correlated with neonicotinoid use, has also been seen in the Netherlands (Hallman et al 2014). This is thought to be due to directly consuming the poisonous seeds (Goulson, 2013) or through the reduction in their insect food source.

Grey Partridge-Cambridge Bird Club

 

Do we need neonicotinoids anyway?

The use of neonicotinoids also appears to have no benefits to agricultural yields of soybean (Myers, 2014), Sunflower and Maize crops (Susuki, 2014). Methods like Integrated Pest Management can reduce the number of pests without the powerful chemicals so isn’t it time we put nature before ease?

More information on the effect on bees

References  painted-lady 

Blacquiere T, Smagghe G, Van Gestel CAM, Mommaerts V. 2012. ` Neonicotinoids in bees: a review on concentrations, side-effects and risk assessment. Ecotoxicology 21:973–992

Brereton TM, Roy DB, Middlebrook I, Botham M, Warren M. 2011. The development of butterfly indicators in the United Kingdom and assessments in 2010. Journal of Insect Conservation 15:139–151

Cresswell JE. 2011. A meta-analysis of experiments testing the effects of a neonicotinoid insecticide (imidacloprid) on honey bees. Ecotoxicology 20:149–157

Defra. 2014. Pesticide usage statistics. Available at https://secure.fera.defra.gov.uk/pusstats/ (accessed March 2017).

Gilburn, A.S., Bunnefeld, N., Wilson, J.M., Botham, M.S., Brereton, T.M., Fox, R., and Goulson, D. (2015). Are neonicotinoid insecticides driving declines of widespread butterflies? PeerJ:e1402

Goulson, D. (2013). An overview of the environmental risk posed by neonicotinoid insecticides. J. Appl. Ecol. 50, 977-987

Hallmann CA, Foppen RPB, Van Turnhout CAM, De Kroon H, Jongejans E. 2014. Declines in insectivorous birds are associated with high neonicotinoid concentrations. Nature 511:341–343

Myers, C., Hill, E. (2014). Benefits of Neonicotinoid Seed Treatments to Soybean Production. US Environmental protection agency

Rundlof M, Andersson GKS, Bommarco R, Fries I, Hederstrom V, Jonsson O, Klatt BK, ¨ Pedersen TR, Yourstone J, Smith HG. 2015. Seed coating with a neonicotinoid insecticide negatively affects wild bees. Nature 521:77–80

Susuki, D. (2014). More Bad News for Bees. Available at http://www.ecology.com/2014/10/31/the-new-word-for-bees/ (accessed March 2017)

Word Count [487]

 



Caring for the Community – How Climate Change is Impacting You!

Posted on by Kirsty State

Global warming has resulted in many species responding and behaving differently.  These changes can impact communities of plants, animals, people, in fact, all species that interact with each other within an environment.

Responses by different species to climate change are all connected through the interactions and shared resources of an ecosystem.  Overall earlier life events, such as flowering, feeding and hatching, are being recorded (Walther, 2010).  However, species do not respond equally to environmental changes.  This can result in timings of species interactions being off as a result of varying degrees of responses to temperature changes

The species found at certain locations are determined by three “filters”:

  • Dispersal
  • Environmental
  • Interactions

These filters are based around interacting species and their tolerance to specific environmental conditions (Götzenberger et al., 2012).  Global warming can be seen as an environmental filter (Weiher et al., 1998).  The increase in temperature could result in species being more or less tolerant of the increased temperature and therefore could change the collection of species in a community.

Climate change is occurring all over the planet, with certain ecosystems being particularly sensitive to it…

Take, for example, the tundra.  This is the area that borders the arctic, where species have to adapt to low temperatures with high variation.  Warming can result in many changes in this area.  Evidence from Alaska shows that climate change can influence land cover (Hinzman et al., 2005). This is through the increasingly more temperate climate, which allows species to grow in less hostile areas which were previously too cold or dry.

rein

Reindeer herd moving across their snowy calving grounds in the Mackenzie Delta, Canada (Dory, n.d)

Reindeer and Caribou species have been increasing in number in northern latitudes.  These play an important role in communities as they are often the largest, most numerous herbivores in an area.  As seen in the diagram below, the species are both affected by climate change impacts on the ecosystem as well as changing the ecosystem themselves.  Their impact on the environment has the potential to cause a vegetation transition (Bernes et al., 2015).  This could result in a knock on effect to other species that also feed off the vegetation eaten by Reindeer and Caribou.

flow-diagram

Flow diagram showing how increased temperatures affects vegetation and large herbivores

Another example is the plant-pollinator relationship that is disrupted by increasing temperature.  Both pollinators and the plants they pollinate, are changing their feeding and flowering times, respectively, at similar rates.  However, these rates are not exactly equal, resulting in a mismatch in the timings (Hegland et al., 2009).  Consequences of this mismatch are that pollination is not as efficient as it could be and that both plant and pollinators numbers are at risk.  This can have bottom up effect on the ecosystem, especially on species (such as humans) that rely on crops that are pollinated as a source of food (Walther, 2010).

bee-and-flower

Bumblebee pollinating a Dahlia ‘Moonfire’ plant (Photo by Kirsty State, 2015).

From these case studies it is important to note that not only is climate change impacting specific species that respond to temperature change, but through a network of communities and interactions within an ecosystem, it can indirectly affect us all.

 

 

Word count: 494

References

Bernes, C., Bråthen, K.A., Forbes, B.C., Speed, J.D. and Moen, J., 2015. What are the impacts of reindeer/caribou (Rangifer tarandus L.) on arctic and alpine vegetation? A systematic review. Environmental Evidence, 4(1), p.1-26.

Dory, N., n.d.  The reindeer of the Mackenzie Delta, Northwest Territories. [photograph] Available at: <http://www.nicolasdory.com/reindeer-of-the-mackenzie-delta/> [Accessed 17 March 2017].

Götzenberger, L., de Bello, F., Bråthen, K.A., Davison, J., Dubuis, A., Guisan, A., Lepš, J., Lindborg, R., Moora, M., Pärtel, M. and Pellissier, L., 2012. Ecological assembly rules in plant communities—approaches, patterns and prospects. Biological reviews, 87(1), pp.111-127.

Hegland, S.J., Nielsen, A., Lázaro, A., Bjerknes, A.L. and Totland, Ø., 2009. How does climate warming affect plant‐pollinator interactions? Ecology letters, 12(2), pp.184-195.

Hinzman, L.D., Bettez, N.D., Bolton, W.R., Chapin, F.S., Dyurgerov, M.B., Fastie, C.L., Griffith, B., Hollister, R.D., Hope, A., Huntington, H.P. and Jensen, A.M., 2005. Evidence and implications of recent climate change in northern Alaska and other arctic regions. Climatic Change, 72(3), pp.251-298.

Walther, G.R., 2010. Community and ecosystem responses to recent climate change. Philosophical Transactions of the Royal Society B: Biological Sciences, 365(1549), pp.2019-2024.

Weiher, E., Clarke, G.P. and Keddy, P.A., 1998. Community assembly rules, morphological dispersion, and the coexistence of plant species. Oikos, 81(2), pp.309-322.