Tour du Valat
Tour du Valat
  • Navigation access
  • Content access
  • Footer access
  • Adopt a flamingo
  • Documentary portal
  • Search
  • fr
  • en
  • The Tour du Valat
    • History and values
    • Luc Hoffmann
    • The estate
    • Our team
    • Organisation chart and CVs
    • Governance and budget
    • Partners and sponsors
    • Hosted organisations
    • Eco-responsibility at the Tour du Valat
    • Visiting the Tour du Valat
  • Mediterranean wetlands
    • Types of Mediterranean wetlands
    • Threats, issues and protection
    • Spotlight on the Camargue
    • The Mediterranean Alliance for Wetlands
    • The Mediterranean Wetlands Observatory
  • Our actions
  • Media
    • The Library
    • Recent publications
    • Activity reports
    • The HAL portal
    • Books, booklets and reports
    • Institutionnal documents
    • Photo gallery
    • Videos
  • News
  • Support us
    • Adopt a Flamingo
    • Make a contribution
    • Make a donation or bequest
  • Navigation access
  • Content access
  • Footer access
  • Adopt a flamingo
  • Documentary portal
  • Search
  • fr
  • en
Tour du Valat
  • The Tour du Valat
    • History and values
    • Luc Hoffmann
    • The estate
    • Our team
    • Organisation chart and CVs
    • Governance and budget
    • Partners and sponsors
    • Hosted organisations
    • Eco-responsibility at the Tour du Valat
    • Visiting the Tour du Valat
  • Mediterranean wetlands
    • Types of Mediterranean wetlands
    • Threats, issues and protection
    • Spotlight on the Camargue
    • The Mediterranean Alliance for Wetlands
    • The Mediterranean Wetlands Observatory
  • Our actions
  • Media
    • The Library
    • Recent publications
    • Activity reports
    • The HAL portal
    • Books, booklets and reports
    • Institutionnal documents
    • Photo gallery
    • Videos
  • News
  • Support us
    • Adopt a Flamingo
    • Make a contribution
    • Make a donation or bequest
Research institute for the conservation of Mediterranean wetlands
  • Home
  • Stay informed
  • Agenda
  • Séminaire sur "La dynamique des populations de canards de prairies est-elle limitée par leur succès reproducteur ou par leur propension à se reproduire?"
Back to Agenda
  • A- Switch to smaller font size
  • A+ Switch to biggest font size
  • Print
  • Share
  • RSS
Seminars December 13, 2010

Séminaire sur "La dynamique des populations de canards de prairies est-elle limitée par leur succès reproducteur ou par leur propension à se reproduire?"

Lundi 13 décembre à 11h, Michael Eichholz (Southern Illinois University) présentera à la Tour du Valat un séminaire intitulé ” La dynamique des populations de canards de prairies est-elle limitée par leur succès reproducteur ou par leur propension à se reproduire?”

Currently, populations of ground nesting ducks in the prairie pothole region of North America are thought to be most limited by their ability to nest successfully. Thus, current management actions emphasize the need to increase nesting success (proportion of nests that hatch at least 1 egg). Assuming nest success most limits populations is based on observations of what are perceived to be extremely low nest success and a linear (non-density dependent) stage based population model. This assumption, however, has yet to be tested with empirical data. Harvest ratio data indicate productivity of both prairie and boreal nesting ducks is density dependent. In fact, it appears the strength of the density dependent signal has increased since implementation of the North American Waterfowl Management Plan that initiated the conversion of millions of acres of agricultural habitat to nesting cover. This indicates current management activities are not addressing the density dependent factor that I argue is most limiting the population. An alternative vital rate that might be more limiting and more likely to be density dependent is breeding probability. The probability of breeding may be < 100% in ducks due to lack of nutrients for egg production and incubation or a lack of secure nesting habitat. Breeding probability has been demonstrated in geese to be dependent on the female’s ability to acquire nutrient reserves prior to breeding. North American ducks also acquire nutrient reserves prior to breeding but some have argued that those reserves are acquired for migration and are unnecessary for the initiation of nesting. I present evidence ducks are acquiring nutrient reserves both early and late in spring migration, indicating the nutrient reserve are being acquired specifically for reproduction. This supports the hypothesis nutrient acquisition may be limiting breeding probability in ducks. Breeding probability may also be limited by safe nesting sites. Unlike geese which incur relatively minor costs of reproduction, about 25% of female prairie-nesting ducks are consumed by predators each year. Thus, reproduction in ducks is quite risky and costly. If ducks are able to recognize this cost and modify their reproductive investment accordingly, it is possible they modify their reproductive investment to the point they skip breeding altogether in years when they are forced to nest in suboptimal habitat. Through an experimental manipulation of nest predator density, I provide evidence hens are able to assess likelihood of successfully hatching a clutch and modify their nesting behavior accordingly. This result indicates hens modify their reproductive investment based on likelihood of successfully nesting and suggests modification of reproductive investment as an addition alternative explanation for the density dependent signal in duck productivity.

Newsletter

Keep up with Tour du Valat news:
Show previous newsletters
News Archives
  • 2025
  • 2024
  • 2023
  • 2022
  • 2021
  • 2020
  • 2019
  • 2018
  • 2017
  • 2016
  • 2015
  • 2014
  • 2013
Agenda Archives
  • 2024
  • 2023
  • 2022
  • 2021
  • 2020
  • 2019
  • 2018
  • 2017
  • 2016
  • 2015
  • 2014
  • 2013
Tour du Valat
Tour du Valat

Le Sambuc - 13200 Arles
France

Phone : +33 (0)4 90 97 20 13

[email protected]


Contact
  • Practical information
    • Calendar
    • Past events
    • Vacancies
    • Interactive map
    • Logo & access map
  • Legal information
    • Legal notice
    • Cookie policy (EU)
  • Linkedin
  • Facebook
  • Vimeo
  • RSS
Gérer le consentement aux cookies
We use cookies to enhance your experience on our web site.
Functional Always active
The technical storage or access is strictly necessary for the legitimate purpose of enabling the use of a specific service explicitly requested by the subscriber or user, or for the sole purpose of carrying out the transmission of a communication over an electronic communications network.
Settings
Le stockage ou l’accès technique est nécessaire dans la finalité d’intérêt légitime de stocker des préférences qui ne sont pas demandées par l’abonné ou l’utilisateur.
Statistics
The technical storage or access that is used exclusively for statistical purposes. Le stockage ou l’accès technique qui est utilisé exclusivement dans des finalités statistiques anonymes. En l’absence d’une assignation à comparaître, d’une conformité volontaire de la part de votre fournisseur d’accès à internet ou d’enregistrements supplémentaires provenant d’une tierce partie, les informations stockées ou extraites à cette seule fin ne peuvent généralement pas être utilisées pour vous identifier.
Marketing
The technical storage or access is required to create user profiles to send advertising, or to track the user on a website or across several websites for similar marketing purposes.
Manage options Manage services Manage {vendor_count} vendors Read more about these purposes
See settings
{title} {title} {title}