Chart and table of population level and growth rate for the Madison metro area from 1950 to 2025.

About this dataset

Context

The dataset tabulates the Madison population over the last 20 plus years. It lists the population for each year, along with the year on year change in population, as well as the change in percentage terms for each year. The dataset can be utilized to understand the population change of Madison across the last two decades. For example, using this dataset, we can identify if the population is declining or increasing. If there is a change, when the population peaked, or if it is still growing and has not reached its peak. We can also compare the trend with the overall trend of United States population over the same period of time.

Key observations

In 2023, the population of Madison was 280,305, a 1.04% increase year-by-year from 2022. Previously, in 2022, Madison population was 277,414, an increase of 1.80% compared to a population of 272,520 in 2021. Over the last 20 plus years, between 2000 and 2023, population of Madison increased by 70,692. In this period, the peak population was 280,305 in the year 2023. The numbers suggest that the population has not reached its peak yet and is showing a trend of further growth. Source: U.S. Census Bureau Population Estimates Program (PEP).

Content

When available, the data consists of estimates from the U.S. Census Bureau Population Estimates Program (PEP).

Data Coverage:

• From 2000 to 2023

Variables / Data Columns

• Year: This column displays the data year (Measured annually and for years 2000 to 2023)
• Population: The population for the specific year for the Madison is shown in this column.
• Year on Year Change: This column displays the change in Madison population for each year compared to the previous year.
• Change in Percent: This column displays the year on year change as a percentage. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Year. You can refer the same here

Graph and download economic data for Employed Persons in Madison, WI (MSA) (LAUMT553154000000005) from Jan 1990 to Apr 2025 about Madison, WI, household survey, employment, persons, and USA.

About this dataset

Context

The dataset tabulates the data for the Madison, WI population pyramid, which represents the Madison population distribution across age and gender, using estimates from the U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates. It lists the male and female population for each age group, along with the total population for those age groups. Higher numbers at the bottom of the table suggest population growth, whereas higher numbers at the top indicate declining birth rates. Furthermore, the dataset can be utilized to understand the youth dependency ratio, old-age dependency ratio, total dependency ratio, and potential support ratio.

Key observations

• Youth dependency ratio, which is the number of children aged 0-14 per 100 persons aged 15-64, for Madison, WI, is 18.8.
• Old-age dependency ratio, which is the number of persons aged 65 or over per 100 persons aged 15-64, for Madison, WI, is 17.3.
• Total dependency ratio for Madison, WI is 36.1.
• Potential support ratio, which is the number of youth (working age population) per elderly, for Madison, WI is 5.8.

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates.

Age groups:

• Under 5 years
• 5 to 9 years
• 10 to 14 years
• 15 to 19 years
• 20 to 24 years
• 25 to 29 years
• 30 to 34 years
• 35 to 39 years
• 40 to 44 years
• 45 to 49 years
• 50 to 54 years
• 55 to 59 years
• 60 to 64 years
• 65 to 69 years
• 70 to 74 years
• 75 to 79 years
• 80 to 84 years
• 85 years and over

Variables / Data Columns

• Age Group: This column displays the age group for the Madison population analysis. Total expected values are 18 and are define above in the age groups section.
• Population (Male): The male population in the Madison for the selected age group is shown in the following column.
• Population (Female): The female population in the Madison for the selected age group is shown in the following column.
• Total Population: The total population of the Madison for the selected age group is shown in the following column.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Age. You can refer the same here

About this dataset

Context

The dataset tabulates the Madison population by year. The dataset can be utilized to understand the population trend of Madison.

Content

The dataset constitues the following datasets

• Madison, WI Population Dataset: Yearly Figures, Population Change, and Percent Change Analysis

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Resident Population in Madison, WI (MSA) was 707.60600 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Madison, WI (MSA) reached a record high of 707.60600 in January of 2024 and a record low of 504.04400 in January of 2000. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Madison, WI (MSA) - last updated from the United States Federal Reserve on July of 2025.

About this dataset

Context

The dataset tabulates the Madison population over the last 20 plus years. It lists the population for each year, along with the year on year change in population, as well as the change in percentage terms for each year. The dataset can be utilized to understand the population change of Madison across the last two decades. For example, using this dataset, we can identify if the population is declining or increasing. If there is a change, when the population peaked, or if it is still growing and has not reached its peak. We can also compare the trend with the overall trend of United States population over the same period of time.

Key observations

In 2022, the population of Madison was 272,903, a 1.88% increase year-by-year from 2021. Previously, in 2021, Madison population was 267,871, a decline of 0.90% compared to a population of 270,313 in 2020. Over the last 20 plus years, between 2000 and 2022, population of Madison increased by 63,290. In this period, the peak population was 272,903 in the year 2022. The numbers suggest that the population has not reached its peak yet and is showing a trend of further growth. Source: U.S. Census Bureau Population Estimates Program (PEP).

Content

When available, the data consists of estimates from the U.S. Census Bureau Population Estimates Program (PEP).

Data Coverage:

• From 2000 to 2022

Variables / Data Columns

• Year: This column displays the data year (Measured annually and for years 2000 to 2022)
• Population: The population for the specific year for the Madison is shown in this column.
• Year on Year Change: This column displays the change in Madison population for each year compared to the previous year.
• Change in Percent: This column displays the year on year change as a percentage. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Year. You can refer the same here

Graph and download economic data for Unemployment Rate in Madison, WI (MSA) (LAUMT553154000000003A) from 1990 to 2024 about Madison, WI, household survey, unemployment, rate, and USA.

About this dataset

Context

The dataset tabulates the population of Madison by gender, including both male and female populations. This dataset can be utilized to understand the population distribution of Madison across both sexes and to determine which sex constitutes the majority.

Key observations

There is a slight majority of female population, with 50.05% of total population being female. Source: U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates.

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates.

Scope of gender :

Please note that American Community Survey asks a question about the respondents current sex, but not about gender, sexual orientation, or sex at birth. The question is intended to capture data for biological sex, not gender. Respondents are supposed to respond with the answer as either of Male or Female. Our research and this dataset mirrors the data reported as Male and Female for gender distribution analysis. No further analysis is done on the data reported from the Census Bureau.

Variables / Data Columns

• Gender: This column displays the Gender (Male / Female)
• Population: The population of the gender in the Madison is shown in this column.
• % of Total Population: This column displays the percentage distribution of each gender as a proportion of Madison total population. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Race & Ethnicity. You can refer the same here

Graph and download economic data for Unemployed Persons in Madison, WI (MSA) (LAUMT553154000000004) from Jan 1990 to May 2025 about Madison, WI, household survey, unemployment, persons, and USA.

About this dataset

Context

The dataset tabulates the population of Madison by gender across 18 age groups. It lists the male and female population in each age group along with the gender ratio for Madison. The dataset can be utilized to understand the population distribution of Madison by gender and age. For example, using this dataset, we can identify the largest age group for both Men and Women in Madison. Additionally, it can be used to see how the gender ratio changes from birth to senior most age group and male to female ratio across each age group for Madison.

Key observations

Largest age group (population): Male # 20-24 years (20,793) | Female # 20-24 years (20,520). Source: U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates.

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates.

Age groups:

• Under 5 years
• 5 to 9 years
• 10 to 14 years
• 15 to 19 years
• 20 to 24 years
• 25 to 29 years
• 30 to 34 years
• 35 to 39 years
• 40 to 44 years
• 45 to 49 years
• 50 to 54 years
• 55 to 59 years
• 60 to 64 years
• 65 to 69 years
• 70 to 74 years
• 75 to 79 years
• 80 to 84 years
• 85 years and over

Scope of gender :

Please note that American Community Survey asks a question about the respondents current sex, but not about gender, sexual orientation, or sex at birth. The question is intended to capture data for biological sex, not gender. Respondents are supposed to respond with the answer as either of Male or Female. Our research and this dataset mirrors the data reported as Male and Female for gender distribution analysis.

Variables / Data Columns

• Age Group: This column displays the age group for the Madison population analysis. Total expected values are 18 and are define above in the age groups section.
• Population (Male): The male population in the Madison is shown in the following column.
• Population (Female): The female population in the Madison is shown in the following column.
• Gender Ratio: Also known as the sex ratio, this column displays the number of males per 100 females in Madison for each age group.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Gender. You can refer the same here

Graph and download economic data for Civilian Labor Force in Madison, WI (MSA) (LAUMT553154000000006A) from 1990 to 2024 about Madison, civilian, WI, labor force, labor, household survey, and USA.

About this dataset

Context

The dataset tabulates the population of Madison by race. It includes the population of Madison across racial categories (excluding ethnicity) as identified by the Census Bureau. The dataset can be utilized to understand the population distribution of Madison across relevant racial categories.

Key observations

The percent distribution of Madison population by race (across all racial categories recognized by the U.S. Census Bureau): 76.11% are white, 6.83% are Black or African American, 0.33% are American Indian and Alaska Native, 8.93% are Asian, 0.04% are Native Hawaiian and other Pacific Islander, 1.57% are some other race and 6.20% are multiracial.

https://i.neilsberg.com/ch/madison-wi-population-by-race.jpeg" alt="Madison population by race">

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Racial categories include:

• White
• Black or African American
• American Indian and Alaska Native
• Asian
• Native Hawaiian and Other Pacific Islander
• Some other race
• Two or more races (multiracial)

Variables / Data Columns

• Race: This column displays the racial categories (excluding ethnicity) for the Madison
• Population: The population of the racial category (excluding ethnicity) in the Madison is shown in this column.
• % of Total Population: This column displays the percentage distribution of each race as a proportion of Madison total population. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Race & Ethnicity. You can refer the same here

About this dataset

Context

The dataset tabulates the data for the Madison, WI population pyramid, which represents the Madison population distribution across age and gender, using estimates from the U.S. Census Bureau American Community Survey 5-Year estimates. It lists the male and female population for each age group, along with the total population for those age groups. Higher numbers at the bottom of the table suggest population growth, whereas higher numbers at the top indicate declining birth rates. Furthermore, the dataset can be utilized to understand the youth dependency ratio, old-age dependency ratio, total dependency ratio, and potential support ratio.

Key observations

• Youth dependency ratio, which is the number of children aged 0-14 per 100 persons aged 15-64, for Madison, WI, is 19.0.
• Old-age dependency ratio, which is the number of persons aged 65 or over per 100 persons aged 15-64, for Madison, WI, is 16.4.
• Total dependency ratio for Madison, WI is 35.4.
• Potential support ratio, which is the number of youth (working age population) per elderly, for Madison, WI is 6.1.

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Age groups:

• Under 5 years
• 5 to 9 years
• 10 to 14 years
• 15 to 19 years
• 20 to 24 years
• 25 to 29 years
• 30 to 34 years
• 35 to 39 years
• 40 to 44 years
• 45 to 49 years
• 50 to 54 years
• 55 to 59 years
• 60 to 64 years
• 65 to 69 years
• 70 to 74 years
• 75 to 79 years
• 80 to 84 years
• 85 years and over

Variables / Data Columns

• Age Group: This column displays the age group for the Madison population analysis. Total expected values are 18 and are define above in the age groups section.
• Population (Male): The male population in the Madison for the selected age group is shown in the following column.
• Population (Female): The female population in the Madison for the selected age group is shown in the following column.
• Total Population: The total population of the Madison for the selected age group is shown in the following column.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Age. You can refer the same here

U.S. Census Bureau QuickFacts statistics for Madison city, Wisconsin. QuickFacts data are derived from: Population Estimates, American Community Survey, Census of Population and Housing, Current Population Survey, Small Area Health Insurance Estimates, Small Area Income and Poverty Estimates, State and County Housing Unit Estimates, County Business Patterns, Nonemployer Statistics, Economic Census, Survey of Business Owners, Building Permits.

About this dataset

Context

The dataset tabulates the data for the Madison, WI population pyramid, which represents the Madison population distribution across age and gender, using estimates from the U.S. Census Bureau American Community Survey (ACS) 2018-2022 5-Year Estimates. It lists the male and female population for each age group, along with the total population for those age groups. Higher numbers at the bottom of the table suggest population growth, whereas higher numbers at the top indicate declining birth rates. Furthermore, the dataset can be utilized to understand the youth dependency ratio, old-age dependency ratio, total dependency ratio, and potential support ratio.

Key observations

• Youth dependency ratio, which is the number of children aged 0-14 per 100 persons aged 15-64, for Madison, WI, is 18.8.
• Old-age dependency ratio, which is the number of persons aged 65 or over per 100 persons aged 15-64, for Madison, WI, is 17.4.
• Total dependency ratio for Madison, WI is 36.2.
• Potential support ratio, which is the number of youth (working age population) per elderly, for Madison, WI is 5.8.

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2018-2022 5-Year Estimates.

Age groups:

• Under 5 years
• 5 to 9 years
• 10 to 14 years
• 15 to 19 years
• 20 to 24 years
• 25 to 29 years
• 30 to 34 years
• 35 to 39 years
• 40 to 44 years
• 45 to 49 years
• 50 to 54 years
• 55 to 59 years
• 60 to 64 years
• 65 to 69 years
• 70 to 74 years
• 75 to 79 years
• 80 to 84 years
• 85 years and over

Variables / Data Columns

• Age Group: This column displays the age group for the Madison population analysis. Total expected values are 18 and are define above in the age groups section.
• Population (Male): The male population in the Madison for the selected age group is shown in the following column.
• Population (Female): The female population in the Madison for the selected age group is shown in the following column.
• Total Population: The total population of the Madison for the selected age group is shown in the following column.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Age. You can refer the same here

About this dataset

Context

The dataset tabulates the Madison population distribution across 18 age groups. It lists the population in each age group along with the percentage population relative of the total population for Madison. The dataset can be utilized to understand the population distribution of Madison by age. For example, using this dataset, we can identify the largest age group in Madison.

Key observations

The largest age group in Madison, WI was for the group of age 20 to 24 years years with a population of 41,313 (14.99%), according to the ACS 2019-2023 5-Year Estimates. At the same time, the smallest age group in Madison, WI was the 85 years and over years with a population of 3,815 (1.38%). Source: U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates

Age groups:

• Under 5 years
• 5 to 9 years
• 10 to 14 years
• 15 to 19 years
• 20 to 24 years
• 25 to 29 years
• 30 to 34 years
• 35 to 39 years
• 40 to 44 years
• 45 to 49 years
• 50 to 54 years
• 55 to 59 years
• 60 to 64 years
• 65 to 69 years
• 70 to 74 years
• 75 to 79 years
• 80 to 84 years
• 85 years and over

Variables / Data Columns

• Age Group: This column displays the age group in consideration
• Population: The population for the specific age group in the Madison is shown in this column.
• % of Total Population: This column displays the population of each age group as a proportion of Madison total population. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison Population by Age. You can refer the same here

About this dataset

Context

The dataset tabulates the Madison town population over the last 20 plus years. It lists the population for each year, along with the year on year change in population, as well as the change in percentage terms for each year. The dataset can be utilized to understand the population change of Madison town across the last two decades. For example, using this dataset, we can identify if the population is declining or increasing. If there is a change, when the population peaked, or if it is still growing and has not reached its peak. We can also compare the trend with the overall trend of United States population over the same period of time.

Key observations

In 2022, the population of Madison town was 6,109, a 1.45% decrease year-by-year from 2021. Previously, in 2021, Madison town population was 6,199, a decline of 0.72% compared to a population of 6,244 in 2020. Over the last 20 plus years, between 2000 and 2022, population of Madison town decreased by 332. In this period, the peak population was 6,656 in the year 2016. The numbers suggest that the population has already reached its peak and is showing a trend of decline. Source: U.S. Census Bureau Population Estimates Program (PEP).

https://i.neilsberg.com/ch/population-of-madison-town-wi-population-by-year-2000-2022.jpeg" alt="Madison town population by year">

Content

When available, the data consists of estimates from the U.S. Census Bureau Population Estimates Program (PEP).

Data Coverage:

• From 2000 to 2022

Variables / Data Columns

• Year: This column displays the data year (Measured annually and for years 2000 to 2022)
• Population: The population for the specific year for the Madison town is shown in this column.
• Year on Year Change: This column displays the change in Madison town population for each year compared to the previous year.
• Change in Percent: This column displays the year on year change as a percentage. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Madison town Population by Year. You can refer the same here

Premise of the study: Shifts in abiotic factors can affect many plant traits, including floral volatiles. This study examines the response of floral volatiles to water availability, and whether phenotypic plasticity to water differs among populations. Furthermore, it investigates genetic differentiation in floral volatiles, determines the effect of temperature on phenotypic plasticity to water, and assesses temporal variation in floral scent emission between day and evening, since pollinator visitation differs at those times. Methods: Rocky Mountain columbine plants (Aquilegia coerulea), started from seeds collected in three wild populations in Colorado, Utah, and Arizona, were grown under two water treatments in a greenhouse in Madison, Wisconsin, USA. One population was also grown under the two water treatments, at two temperatures. Air samples were collected from enclosed flowers using dynamic headspace methods and floral volatiles were identified and quantified by gas chromatography (GC) with mass spectrometry (MS) detection. Key Results: Emission of three floral volatiles increased in the wetter environment, indicating phenotypic plasticity. The response of six floral volatiles to water differed among populations, suggesting genetic differentiation in phenotypic plasticity. Five floral volatiles varied among populations, and emission of most floral volatiles was greater during the day. Conclusions: Phenotypic plasticity to water permits a quick response of floral volatiles in changing environments. The genetic differentiation in phenotypic plasticity suggests that phenotypic plasticity can evolve but complicates predictions of the effects of environmental changes on a plant and its pollinators. Methods Plants from the three populations were grown from seeds in one room, kept at 20° C during the day and 7.7° C at night, at the Walnut Street greenhouses in Madison, Wisconsin (the cool room). Plants for the CO population were also grown in a warm room kept at 25.5° C during the day, and 13.3° C at night, which represented a difference from the cool room of 5.5° C during the day, and 5.6° C at night. The temperature regime was linked to the light regime in the greenhouse rooms. Within each room, plants within populations were randomly assigned to an every fifth (wet) or every eighth day (dry) water treatment. The same volume of water was added to each plant on a given day, and only the frequency of watering changed between the two water treatments. These two water treatments represented unstressed and stressed conditions. Plants were grown for about four months in their respective treatments, and when most plants had ten leaves, they were vernalized for 2 months at 4º C to trigger flowering before being returned to their respective greenhouse room. While flowering time varied with temperature and water treatment (Brunet and Larson- Rabin, 2012), most plants started flowering 2.5-3 months after being returned to their respective treatments. To measure the volatiles emitted from columbine flowers, we collected air samples from enclosed flowers using dynamic headspace methods and identified and quantified compounds by gas chromatography (GC) with mass spectrometry (MS) detection. Volatiles were collected from a single receptive female flower per plant, and from up to seven plants per day for most days between March 22 and April 10. We used a chiral GC column in order to separate and measure optical enantiomers of some of the floral volatiles. We examined the impact of population and water at low temperature; the impact of water at two temperatures for the Colorado population, and examined the temporal variation in floral volatile emission between day and evening (including dusk) because hawkmoths tend to visit these plants at dusk.

Bottlenecks, founder events, and genetic drift often result in decreased genetic diversity and increased population differentiation. These events may follow abundance declines due to natural or anthropogenic perturbations, where translocations may be an effective conservation strategy to increase population size. American black bears (Ursus americanus) were nearly extirpated from the Central Interior Highlands, USA by 1920. In an effort to restore bears, 254 individuals were translocated from Minnesota, USA and Manitoba, Canada, into the Ouachita and Ozark Mountains from 1958 to 1968. Using 15 microsatellites and mitochondrial haplotypes, we observed contemporary genetic diversity and differentiation between the source and supplemented populations. We inferred four genetic clusters: Source, Ouachitas, Ozarks, and a cluster in Missouri where no individuals were translocated. Coalescent models using approximate Bayesian computation identified an admixture model as having the highest posterior probability (0.942) over models where the translocation was unsuccessful or acted as a founder event. Nuclear genetic diversity was highest in the source (A = 9.11) and significantly lower in the translocated populations (A = 7.07 - 7.34; P = 0.004). The Missouri cluster had the lowest genetic diversity (A = 5.48) and served as a natural experiment showing the utility of translocations to increase genetic diversity following demographic bottlenecks. Differentiation was greater between the two admixed populations than between the source, suggesting that genetic drift acted strongly over the eight generations since the translocation. The Ouachitas and Missouri were previously hypothesized to be remnant lineages. We observed a pre-translocation remnant signature in Missouri but not in the Ouachitas.