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Investigating Flower Constancy in Bumble bees (Bombus terrestris)

Varadarajan, Vidula (2020) BION02 20192
Degree Projects in Biology
Abstract
Current land use change and habitat fragmentation have caused severe decline in bumble bee populations. In order to address this issue and plan future conservation measures and strategies for plant pollinator networks, it is important to understand their foraging behaviour. A few studies in the past have tried to understand foraging constancy in bumble bees. However, there is no clear information on how flower constant bumble bees are over time and how this affects their population in the context of changing spatial and temporal resource distribution. This study aimed to investigate flower constancy over time between and within Bombus terrestris individuals using a novel AI identification technique for pollen identification. In addition,... (More)
Current land use change and habitat fragmentation have caused severe decline in bumble bee populations. In order to address this issue and plan future conservation measures and strategies for plant pollinator networks, it is important to understand their foraging behaviour. A few studies in the past have tried to understand foraging constancy in bumble bees. However, there is no clear information on how flower constant bumble bees are over time and how this affects their population in the context of changing spatial and temporal resource distribution. This study aimed to investigate flower constancy over time between and within Bombus terrestris individuals using a novel AI identification technique for pollen identification. In addition, it aimed to study if the bumble bee individuals collected pollen within the 300 m vicinity from their nest. It was also found that constancy goes down over time and that B. terrestris individuals have a large forage area. This result is supported by past studies where B. terrestris individuals travel as far as 1000 m to collect pollen. This information provides useful insights about the bumble bee foraging behaviour and can help in improving conservation management measures of bumble bees. (Less)
Popular Abstract
Investigating Flower constancy in Bumble bees

Bumble bees feed on many different plant species. However, they tend to focus on few or specific plant species to increase their foraging efficiency. This phenomenon is called flower constancy. The plants also benefit from flower constancy, as correct pollen type reaches the plant, ultimately leading to successful sexual reproduction of the plant. How changes in the landscape affect bumble bee’s foraging constancy?

The foraging bumble bees were caught and marked with number plate stuck on their thorax. Following the marking, the pollen was collected from them. These pollen samples were then prepared with a staining gel and ethanol. Finally, the pollen samples were scanned. The pollen... (More)
Investigating Flower constancy in Bumble bees

Bumble bees feed on many different plant species. However, they tend to focus on few or specific plant species to increase their foraging efficiency. This phenomenon is called flower constancy. The plants also benefit from flower constancy, as correct pollen type reaches the plant, ultimately leading to successful sexual reproduction of the plant. How changes in the landscape affect bumble bee’s foraging constancy?

The foraging bumble bees were caught and marked with number plate stuck on their thorax. Following the marking, the pollen was collected from them. These pollen samples were then prepared with a staining gel and ethanol. Finally, the pollen samples were scanned. The pollen species were identified by analysing scanned images with the help of a novel AI software.

Human activities are transforming the surroundings. Bumble bees encounter varying flowers during different seasons. Responding to these changes the bumble bees have become inconstant over their lifetime. It was exciting for us to get this result as it is contradicting to the expectation that bumble bees are constant flower foragers.

How far away from their hive do they travel to collect pollen?
Bumble bees travel very far to collect their preferred pollen species. However, these preferred pollen species change over time. Some bumble bee species can travel as far as 1 km. Although they sometimes travel far to collect their pollen, they still collect majority amount of pollen close to 300 m distance from their hive as found in this study.

Landscape changes have caused a decline in bumble bee population. These changes have modified flower resources in the bumble bee’s surroundings and have changed their foraging behaviour. The bumble bees are known to provide useful services to man like pollination. However, the current drastic landscape changes threaten their survival. It is necessary to preserve their surroundings with abundant and favourable flower resources in order to plan effective conservation measures for the bumble bees.

Master’s Degree Project in Biology 45 credits 2020
Department of Biology, Lund University

Advisor: Ola Olsson
Advisors Biodiversity Unit, Department of Biology
Co-advisor: Johanna Yourstone
Advisors Biodiversity Unit, Department of Biology (Less)
Please use this url to cite or link to this publication:
author
Varadarajan, Vidula
supervisor
organization
course
BION02 20192
year
type
H2 - Master's Degree (Two Years)
subject
language
English
id
9030990
date added to LUP
2020-10-16 10:26:35
date last changed
2020-10-16 10:26:35
@misc{9030990,
  abstract     = {Current land use change and habitat fragmentation have caused severe decline in bumble bee populations. In order to address this issue and plan future conservation measures and strategies for plant pollinator networks, it is important to understand their foraging behaviour. A few studies in the past have tried to understand foraging constancy in bumble bees. However, there is no clear information on how flower constant bumble bees are over time and how this affects their population in the context of changing spatial and temporal resource distribution. This study aimed to investigate flower constancy over time between and within Bombus terrestris individuals using a novel AI identification technique for pollen identification. In addition, it aimed to study if the bumble bee individuals collected pollen within the 300 m vicinity from their nest. It was also found that constancy goes down over time and that B. terrestris individuals have a large forage area. This result is supported by past studies where B. terrestris individuals travel as far as 1000 m to collect pollen. This information provides useful insights about the bumble bee foraging behaviour and can help in improving conservation management measures of bumble bees.},
  author       = {Varadarajan, Vidula},
  language     = {eng},
  note         = {Student Paper},
  title        = {Investigating Flower Constancy in Bumble bees (Bombus terrestris)},
  year         = {2020},
}