title: The compounding effects of high pollen limitation, selfing rates and inbreeding depression leave a New Zealand tree with few viable offspring.
abstract: OBJECTIVE
  Interactions between species are especially sensitive to environmental changes. The interaction between plants and pollinators is of particular interest given the potential current global decline in pollinators. Reduced pollinator services can be compensated for in some plant species by self-pollination. However, if inbreeding depression is high, selfed progeny could die prior to reaching adulthood, leading to cryptic recruitment failure.
  
  
  METHODS
  To examine this scenario, pollinator abundance, pollen limitation, selfing rates and inbreeding depression were examined in 12 populations of varying disturbance levels in Sophora microphylla (Fabaceae), an endemic New Zealand tree species.
  
  
  RESULTS
  High pollen limitation was found in all populations (average of 58 % reduction in seed production, nine populations), together with high selfing rates (61 % of offspring selfed, six populations) and high inbreeding depression (selfed offspring 86 % less fit, six populations). Pollen limitation was associated with lower visitation rates by the two endemic bird pollinators.
  
  
  CONCLUSIONS
  The results suggest that for these populations, over half of the seeds produced are genetically doomed. This reduction in the fitness of progeny due to reduced pollinator service is probably important to population dynamics of other New Zealand species. More broadly, the results suggest that measures of seed production or seedling densities may be a gross overestimate of the effective offspring production. This could lead to cryptic recruitment failure, i.e. a decline in successful reproduction despite high progeny production. Given the global extent of pollinator declines, cryptic recruitment failure may be widespread.
authors.affiliation: Institute of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North, New Zealand, mymegy@gmail.com.
authors.forename: Megan L
authors.initials: ML
authors.lastname: Van Etten
authors.affiliation: Institute of Fundamental Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
authors.forename: Jennifer A
authors.initials: JA
authors.lastname: Tate
authors.affiliation: School of Biological Sciences, University of Auckland, Private Bag 92019, Auckland, New Zealand.
authors.forename: Sandra H
authors.initials: SH
authors.lastname: Anderson
authors.affiliation: School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
authors.forename: Dave
authors.initials: D
authors.lastname: Kelly
authors.affiliation: School of Biological Sciences, University of Canterbury, Private Bag 4800, Christchurch 8140, New Zealand.
authors.forename: Jenny J
authors.initials: JJ
authors.lastname: Ladley
authors.affiliation: School of Science and Technology, Open Polytechnic of New Zealand, Private Bag 31914, Lower Hutt 5040, New Zealand and.
authors.forename: Merilyn F
authors.initials: MF
authors.lastname: Merrett
authors.affiliation: Landcare Research, Massey University, Private Bag 11052, Palmerston North, New Zealand.
authors.forename: Paul G
authors.initials: PG
authors.lastname: Peterson
authors.affiliation: Institute of Agriculture and Environment, Massey University, Private Bag 11222, Palmerston North, New Zealand.
authors.forename: Alastair W
authors.initials: AW
authors.lastname: Robertson
mesh_terms: D007178:Inbreeding; D009520:New Zealand; D054817:Pollination; D011157:Population Dynamics; D057945:Self-Fertilization; D029909:Sophora / Q000235:genetics / Q000502:physiology*
keywords: Cryptic recruitment failure; Kowhai; Meliphagidae; Sophora microphylla; inbreeding depression; mating system; pollen limitation; pollinator decline; reproductive ecology