Fitness costs and benefits of a non-native floral resource for subalpine solitary bees

Organisms inhabiting seasonal environments must fit their life cycle into a limited time window while also synchronizing periods of resource consumption with timing of resource availability. Introduced non-native species, which often differ in phenology from natives, can alter and expand the seasonal window of resource availability for native consumers, providing potential fitness benefits. However, if these non-native resources are nutritionally unsuitable for native consumers, their presence could elicit foraging behaviour that proves maladaptive—i.e., they could act as an ecological trap. Here, we used multi-year field observations and a laboratory experiment to investigate the impacts of a common non-native plant species on two components of fitness in three solitary bee species (all specialist consumers of pollen from the plant family Asteraceae) native to the Colorado Rocky Mountains. First, we tested whether individual bees that collect pollen from the non-native common dandelion..., , , # Data from: Fitness costs and benefits of a non-native floral resource for subalpine solitary bees

[https://doi.org/10.5061/dryad.cc2fqz6g9](https://doi.org/10.5061/dryad.cc2fqz6g9)

## Description of the data and file structure

Data were collected to test the extent to which three *Osmia* bee species use pollen from a non-native plant species, *Taraxacum officinale* (common dandelion), and the fitness consequences of their using that pollen. Data were also collected on flowering phenology of native and non-native plants at the study sites, and overwinter survival of bees developing from eggs laid at different times during the summer.

### Files and variables

#### File: Osmia\_2017\_survival\_to\_emergence.txt

**Description:** Data from 2017 on nest initiation and the number of eggs laid by individual bees that survived to emergence in 2019. These data are represented in Fig. 1B of the manuscript.

##### Variables

* Taxon: Bee genus and species observed.
* Subgenus: Subgenus to wh...